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C E fl?l SD1 

University of Texas Bulletin 

No. 1X56: October S. 

The Weno and Pawpaw Formations of the 
Texas Gomanchean 


W. S. AdVins 

On A New Ammonite Fauna of the Lower Turonian 

of Mexico 


Emil Hose 

Bureau of Economic Geology and Technoli gy 

Division of Economic Geology 
. A. Udden, Director of the Bureau and Head of f ?ie Division 





51520 904818-2m 

University of Texas Bulletin 

No. 1856: October 5, 1918 

The Weno and Pawpaw Formations of the 
Texas Gomanchean 


, . ' . - . 

: ; '.' , 

W. S. Adkins 

On A New Ammonite Fauna of the Lower Turonian 

of Mexico 


Emil Hose 

Bureau of Economic Geology and Technology 

Division of Economic Geology 
J. A. Udden. Director of the Bureau and Head of the Division 




The benefits of education and of 
useful knowledge, generally diffused 
through a community, are essential 
to the preservation of a free govern- 

Sam Houston 

Cultivated mind is the guardian 

genius of democracy It is the 

only dictator that freemen acknowl- 
edge and the only security that free- 
men desire. 

Mirabeau B. Lamar 




The Weno and Pawpaw Formations of the 
Texas Gomanchean 


W. S. Adkins 




Rocks underlying the Weno and Pawpaw Formations 

Pre-Comanchean *" 

Comanchean * 4 

Thickness changes 

Lithological changes 

Weno and Pawpaw Formations 

Thickness changes 25 

North-South changes 25 

East-West changes 26 

Lithological changes 

Pawpaw Formation > 

Weno Formation 35 

Stratigraphic Correlation 40 

North Central Texas and Southern Oklahoma 40 

South Central Texas 40 

West Texas and Mexico 41 

Europe and North Africa 4 a 


The Weno Fauna 45 

The Pawpaw Fauna 4 ? 

Comparison of Pyrite Faunae 53 

Texas 53 

Kiamitia Clay Fauna 54 

Duck Creek Marl Fauna 64 

Denton Clay Fauna '. 55 

Grayson Fauna 5(5 

Del Rio Clay Fauna 58 

Summary of Pyrite Faunae 60 

Europe and Africa 



Nautilus texanus Shumard 6S 

Nautilus sp 

Hamites tenawa Adkins and Winton 69 

Hamites sp. aff. armatus Sowerby 

Ancycloceras bendirei n. sp '" 

Hamulina wortkensis n. sp 

Baculites comanchensis n. sp ? 4 

Turrilitcs bosquensis n. Sp 

Turrilites worthensis Adkins and Winton 78 

Turrilites sp 

Scaphites hilli Adkins and Winton 79 

6 University of Texas Bulletin 

Engonoceras serpentinum (Cragin) 8-1 

Engonoceras sp 85 

Flickia boesei n. sp 85 

Flickia (?) bosquensis n. sp 87 

Schloenbachia wenoensis n. sp 89 

Schloenbachia wintoni n. sp 90 

Mortoniceras worthense n. sp 91 

Acanthoceras worthense n. sp 93 


Pentagonaster texensis Adkins and Winton 95 

Metopaster hortensae Adkins and Winton 97 

Comptonia wintoni n. sp. 97 

Pentaceros americanus n. sp 99 


Leiocidaris sp 101 

Goniopygus sp 102 

Pedinopsis symmetries (Cragin) 102 

Peltastes sp 102 

Salenia sp 103 

Cyphosoma volanum Cragin 103 

Holectypus limitis Bose 103 

Holaster sp. aff. simplex Shumard 104 

Epiaster wenoensis n. sp 105 

Epiaster aguilerae Bose 109 

Epiaster subobesus n. sp : 110 

Enallaster wenoensis n. sp 112 

Enallaster bravoensis Bose 114 

Enallaster sp. aff. texanus (Roemer) Hi 

Hemiaster calvini Clark ; 114 

Hemiaster riovistae n. sp 115 


Nucula nokonis n. sp 118 

Nucula wenoensis n. sp 120 

Area washitaensis n. sp 121 

Gervilliopsis invaginata (White) 122 

Ostrea carinata ? Lamarck 122 

Ostrea sp. aff. diluviana Linnaeus 122 

Ostrea (Alectryonia) quadriplicata Shumard 123 

Exogyra sp. aff. arietina Roemer 123 

Pecten inconspicuus Cragin 123 

Pecten georgetownensis Kniker 125 

Venericardia wenoensis n. sp 125 

Protocardia sp. aff. multistriata (Shumard) 126 

Corbula wenoensis n. sp 127 

Corbula basiniformis n. sp *. 130 

Corbula littoralis n. sp ^33 

Cyprimeria washitaensis n. sp 134 

Remondia ? acuminata (Cragin) 13g 

Weno and Pawpaw Formations 


Amberleya graysonensis n. sp 137 

Trochus laticonicus n. sp 138 

Helicocryptua mexicnnus B6ie 139 

Nerita sp 139 

Neritina sp 139 

Anchura mudgeana White 139 

Natica sp 140 

Lunatia sp 140 

Globiconcha sp 140 

Turritella graysonensis n. sp 140 

Turritella worthensis I), sp 142 

Cinulia washitacnsis n. sp 143 


Nodoiaria texana Conrad 145 


PLATES 111. . ..149-170 

8 University of Texas Bulletin 


Figure 1. Map of Texas and part of Oklahoma showing outcrops of the Weno 
and Pawpaw formations, and the lithological facies of the 
Pawpaw formation 11 

Figure 2. Ancycloceras bendirei n. sp., suture of the type individual, camera 

lucida drawing, x 5 71 

Figure 3. Hamulina worthense n. sp., sutures of type individual, camera lucida 

drawing, x 15 73 

Figure 4. Baculites conuanchentis n. sp., sutures of type individual, camera 

lucida drawing, x 8 75 

Figure 5. Turrilites bosquentis n. sp., sutures, type individual, camera lucida 

drawing, x 8 77 

Figure 6. Scaphttes hilli Adkins and Winton, type individual, diagrammatic 
restoration showing orientation and sutures, camera lucida 
drawing, x 12 82 

Figure 7. Scaphites hilli Adkins and Winton, young individual, showing the 

last five sutures, camera lucida drawing, x 10 83 

Figure 8. Scaphite* hilli Adkins and Winton, external and internal suture, 

camera lucida drawing, x 10 84 

Figure 9. Flickia boeiei n. sp., type individual, sutures, camera lucida draw- 
ing, x 8 v 86 

Figure 10. Flickia bosquensis n. sp., diagrammatic projection of sutures of type 

individual, camera lucida drawing, x 5 88 

Figure 11. Schloenbachia wintoni n. sp., type individual, last suture, camera 
lucida drawing, x 5. Keel region slightly distorted in type 
individual r 91 

Figure 12. Mortoniceras worthense n. sp., suture of individual, Plate 1, figure 6, 

camera lucida drawing, x 10 93 

Figure 13. Acanthoceras worthense n. sp., suture, camera lucida drawing, x 8 94 

Plates 1 11. Fossils of the Weno and Pawpaw formations . .149-170 





The Weno and Pawpaw formations are two thin formations lying near 
the top of the Comanchean series of strata, and are most typically developed 
in the region between the Red and the Brazos rivers. The importance of 
these formations, especially the Pawpaw, is much greater than their thick- 
ness would seem to indicate. The Pawpaw is a formation of small thick- 
ness, sharply limited lithologically both above and below, and contains 
a remarkable series of small pyritic fossils which are so sharply charac- 
terized and so distinctive in appearance, even in minute fragments such 
as are encountered in drilling, that this formation should be recognized in 
wells lying to the east of its outcrop and should furnish at least one certain 
and dependable stratigraphic level in the Comanchean. In the hope that 
the formation may have this value, its fauna has been described in some 
detail and the lateral variations in its lithological character indicated. 2 
The same statements hold to a lesser extent for the Weno formation. The 
stratigraphic position of these two formations in the Comanchean series 
and their equivalents in the Central Texas section are given in the fol- 
lowing table. 

The Weno and Pawpaw formations are visible over a small areal extent, 
their outcrops aggregating somewhat more than 100 square miles, mainly 
in a narrow strip in Johnson, Tarrant, Denton, Gooke and Grayson Coun- 
ties, Texas, and Love, Marshall, Bryan and Choctaw Counties, Oklahoma. 
In addition they have stratigraphic equivalents in Central and Western 
Texas and in Mexico, that will be discussed later. Their north-south dis- 
tribution in Texas is between Lat. 32N. and 34N. ; and their east-west 
distribution is practically unknown. In Oklahoma their east-west distri- 
bution is between Long. 9515' and 97 ; and their north-south distribution 
is unknown. The total length of their outcrop north of the Brazos River 

'Manuscript accepted June 15, 1920, published November, 1920. 

"It is hoped that operators and others having well samples suspected of being Upper 
Comanchean will submit them for examination to the Bureau of Economic Geology 
at Austin. 

3 I wish to express my indebtedness to Professor W. M. Winton, with whom the 
preliminary work on these and other Comanchean formations was done jointly. The 
results of these studies will appear in forthcoming papers by both authors. 

10 University of Texas Bulletin 




North of the 
Brazos River 

South of the 
Brazos River 



ofldya.: ' 

.'. ."' '. '-' 






Fort Worth 
Duck Creek marl 
Duck Creek Ls. 



Del Rio 







Comanche Peak 



(Basement Sands) 1 

Travis Peak 




is about 110 miles in Texas and 100 miles in Oklahoma. The outcrop is S- 
shaped, and north and west of its limits in North Central Texas the forma- 
tions are eroded away; while east and south of the outcrop, the Weno- 
Pawpaw rock sheet continues underground for an unknown distance, being 
buried beneath the more recent Comanchean and Cretaceous strata. This 
concealed extension of these formations still awaits exploration by means 
of detailed well logs and the examination of samples from drillings. The 
formations show distinct north-south changes along their outcrops and 
equally distinct east-west changes. As a whole, they thicken moderately 
from the Brazos river (near Blum) north to the Red River (north of 
Gainesville) , and thence eastward down the Red River valley through Den- 

'See also: Bose, University of Texas Bulletin, 1902, p. 16, fig. 1. 

2 The Comanchean sea was transgressive northwards over much of Central Texas, 
and the Basement sand is not a single formation, but at different places is the time 
equivalent of various off-shore formations. 

Hi no and Pawpaw Formations 


Fig. 1. Map of Texas and part of Oklahoma, showing outcrops of the Weno and 
Pawpaw formations and the lithological facies of the Pawpaw formation. 
SI Sandstone and Ironstone; Cl Clay; M Marl; LS Limestone. 

12 University of Texas Bulletin 

ison and Bennington they thicken rapidly ; so that by inference the main 
thickening is ENE. and the lines of equal thickness run about 60 E. of N. 

Southward from the Red River in Cooke County the Weno and Pawpaw 
formations thin gradually to at least the Colorado River where they are 
probably represented by strata lying near the top of the Georgetown lime- 
stone. The two formations behave very differently over the area men- 
tioned. The Weno formation, south of the change of direction of its out- 
crop in Cooke County decreases slightly in thickness, from about 75 feet 
near Gainesville to 65 feet near Fort Worth, 60 near Riovista, 40 near 
Waco, and 20(?) near Georgetown. The Pawpaw clay on the other hand, 
thins more rapidly from the Red River southward. Near Cedar Mills, 
Cooke County it is 60 feet thick, in Denton County 40 feet, at the north 
border of Tarrant County 27 feet, on Sycamore Creek near Fort Worth 24 
feet, at the south border of Tarrant County 12 feet, at Riovista 5 feet, at 
}Blum 3 feet, and near Waco about 2 feet thick. This thinning is a part of 
the general thinning southwards of the softer formations of the North 
Texas Washita, which south of the Brazos are represented in the George- 
town limestone, as is observable in the Kiamitia marl, Duck Creek marl, 
Denton marl, Pawpaw clay and Grayson marl. The alternate harder for- 
mations, the Duck Creek limestone, Fort Worth limestone, Weno limestone, 
Mainstreet limestone, undergo proportionately less thinning southwards 
and hence contribute relatively larger components to the Georgetown lime- 

There are equally distinct differences of lithology and facies, which are 
presented later. 

The present paper is only an introduction to the large and interesting 
Weno and Pawpaw faunae, the majority of whose species are still unde- 
scribed. Much collecting and further study is required before any attempt 
can be made towards a monographic treatment of these fossils. It will be 
noted that the limits set in this paper coincide with the boundaries of hori- 
zons 25 to 33 inclusive, of Adkins and Winton's preliminary section of the 
North Texas Washita division. 1 

1 Adkins and Winton, Paleontological Correlation of the Fredericksburg and Washita 
Formations in North Texas. Univ. Texas Bull. 1945, 1920. 


The stratigraphy of the Weno and Pawpaw formations involves the re- 
gional stratigraphy of the Comanchean area north of the Brazos River, and 
accordingly, certain lithological and structural features of this region will 
be described. 

In almost the whole region in question, along the line of outcrop of these 
two formations between the Brazos and the Red Rivers, the Comanchean 
sediments are deposited over a large geosyncline whose axis is transverse 
to the direction of the Comanchean outcrops i. e., roughly northwest- 
southeast and whose bulk was largely filled in by pre-Comanchean depos- 
its. However, there is a feeble surface reflection of this buried structure, 
which influences the thickness and lithologic characters of all Comanchean 
deposits, including the Weno and Pawpaw formations. The north edge of 
this deep trough is near the. Red River and the south edge is south of the 
Brazos ; the north slope is steep and the south slope more gentle. This de- 
pression, in which the Fort Worth region is located will be called the Fort 
Worth geosyncline. 



Its extent may be indicated by the meager data available on the under- 
ground position of the Ellenburger limestone. At Muenster, Cooke County, 
it was reached at a depth of about 1800 feet, or 1050 feet below sea level. 
At Myra, Cooke County, the Ellenburger was reached at a depth of 1640 
feet below the surface or about -900 feet (sea level). 1 In the Polytechnic 
(Byrens-Burchell No. 1) well near Fort Worth, the Ellenburger if present 
lies below -3950 feet, at which level the Bend has probably not been reached. 
The difference in elevations of the last two subsurface points is 3050 feet 
which represents the minimum change of elevation of the first Ellenburger 
reached between Myra and Fort Worth, in case the Ellenburger is present 
at the latter place. Coincidentally the thickness of Pennsylvanian deposits 
is not more than 600 feet at Myra, but has increased to at least 3600 feet at 
Fort Worth. Other wells in Tarrant and nearby counties have penetrated 
similar Pennsylvanian material. 

Farther south there is doubt that the Ellenburger is present. In the 
Hillsboro well the pre-Cambrian rocks were said to be reached at a depth 

'Matteson, Econ. Geol., XIV, No. 2, p. 1919. 

14 University of Texas Bulletin 

of 2100 feet, apparently without intervening Ellenburger, and at Waco 
th,e pre-Cambrian is present at about 2500 feet. However, at points still 
farther south and southwest, as at Gatesville and Leander, the Ellenburger 
is present but thin, and overlies pre-Cambrian shales or slate-graywacke 
which near Leander are stated to be identical in appearance with the 
Virginia shales and to be of upper Huronian age. 1 At Georgetown, Leon 
Springs and Camp Bullis, 2 the Trinity directly overlies the pre-Cambrian 
schists; 3 the depths of the contact are respectively 1100 feet, 1015 feet, and 
1790 feet. 

The depression which is triangular shaped and narrower to the north- 
west, is flanked to the north, at least in Cooke County, by a structurally 
high area of Ellenburger at -900 feet, and a thin Pennsylvanian ; and to 
the west by the structurally high Bend Arch in which the -3000 and -3500 
Ellenburger contours have a trend east and south. 4 Whether this Ellenbur- 
ger depression opens to the southeast or to the northwest is not known to 
me. It was, however, invaded by the Pennsylvanian seas which deposited 
in its central part at least 3600 feet of sediments, and left a surface which 
was more largely levelled than the original floor. 

Upon this surface the Comanchean sea transgressed from the southeast, 
depositing sediments which still show a feeble reflection of the underlying 


Any pre-Comanchean ridges and valleys over which the Comanchean 
seas spread would be indicated by deposition which is thicker in the valleys 
and thinner over the crests. If therefore we identified a regional thinning 
of the beds in two directions from a given location, this might be attributed 
to deposition on two sides of an existing valley in the ocean bottom, whether 
originally this valley was erosional or synclinal. This lensing is evident in 
the Comanchean formations, and particularly in the lower ones (Glenrose, 
Paluxy) . For example the Glenrose fills in much of the depression by lens- 
ing; at Decatur it is about 35 feet thick but at Fort Worth about 475 feet, 

a By Professor A. W. Johnston, oral communication. 

2 Sellards: The Geology and Mineral Resources of Bexar County, Univ. Texas Bull. 
1932, pp. 19-20. 

'These facts were discovered by Dr. J. A. Udden, who has kindly permitted their 
use here. 

4 SelIards: On the Underground Position of the Ellenburger Formation in North 
Central Texas, Univ. Texas Bull. 1849, 1920. 

Weno and Pawpaw Formations 


and is increasing southeastward at the rate of about 8 feet per mile. (Hill). 
Likewise the Paluxy entirely disappears to the south. There are in addition 
two complicating circumstances, which affect the thickness and lithology, 
general regional thickening and depositional facies. The Fredericksburg 
division increases steadily in thickness from the Red River to beyond the 
Rio Grande. Its marl and marly limestone facies persist at most levels to 





Bryan and Marshall 
? Counties, Oklahoma 

| Grayson County, Texas 

Cooke County 


=> Denton County 

o Tarrant County 

Parker County 


= Johnson County 


5 Hill County 










Mainstreet .... 


10 15 












9 18 





110 ' 













Fort Worth 







25 27 


Duck Creek marl . . . 
Duck Creek limestone 






40 f 












Comanche Peak .... 






















400 -500 

Basement Sand 

s i v e Woodbine . . 

























^Approximate thickness. 

16 University of Texas Bulletin 

the region between the Brazos and the Colorado Rivers. South and west of 
this region the Rudistid facies invades the Fredericksburg division, begin- 
ning with the level representing the top of the Edwards limestone (see page 
24). The Rudistid facies is characterized by considerable thickness of 
indurated massive limestone, so that southward as this facies vertically 
invades the stratigraphic column the invaded formations thicken, Rough 
estimates of the thickness of this division are: Red River (Denison, 50 
feet ; Goodland, Oklahoma, 25 feet) ; Trinity River (Fort Worth), 242 feet; 
Colorado River (Austin), 350 feet. And for the Washita division: Den- 
ison, 541 feet; Fort Worth, 374 feet; Austin, 220 feet. 

In the following table of approximate thicknesses it should be noted that 
the basal Comanchean deposits are transgressive northwards in such a 
manner that we do not know with certainty what part if any of the Base- 
ment Sands of Cooke, Grayson and Denton Counties is of Trinity age. The 
lowest determined Comanchean fossils in this area indicate the level of 
Exogyra texana and its varieties of Walnut age. In the Duck Creek forma- 
tion of the table the "marl" is taken to be the portion above the Mineralized 
Ledge 1 (Stratum 17) of the Fort Worth region, i. e., above the horizon of 
abundance of Scaphites worthensis. 


The lithology of the Washita division is diverse and each formation 
must be considered separately. However, it is generally true in North- 
Central Texas that the formations decrease in thickness southwards to 
the Brazos-Colorado divide south of Waco, Texas ; these changes in thick- 
ness and lithology may be considered as a unit, and are related to the 
depositional conditions in the large North-Central Texas trough already re- 
ferred to. Crossing the Brazos-Colorado Divide in which the thinned Penn- 
sylvanian and Ellenburger and pre-Cambrian floor are structurally high, 
there is in the Cretaceous another set of thickness changes which for cer- 
tain formations, notably the Buda, amount to a regional increment in 
thickness as far south as the turning point of the Washita outcrops in 
Bexar County. Westward from this point there appears a little known set 
of changes in thickness and lithology of these formations. In West Texas 
again, the northern, near-shore facies (Cerro de Muleros, Finlay Moun- 
tains, Kent, Sierra Blanca) passes quickly into the southern, massive 
limestone, in part rudistid facies (Shafter, Terlingua, Fort Stockton, Shef- 
field) and the Texas and Pacific Railway is approximately the boundary 
line between these two facies. The transition zone from the Edwards 

1 Winton and Adkins: The Geology of Tarrant County, Univ. Texas Bull. 1931 
pp. 42-43. 

Weno and Pawpaw Formations 17 

limestone level passes between Fort Stockton and Sheffield and eastward to 
a point near Pecos, thence some distance north of Coke and Runnels coun- 
ties, north of the Central Mineral Region, and approximately to the north- 
ern border of Hood County, near Comanche Peak. Here the Edwards out- 
crop disappears eastward under the later formations. An extended study 
of the rudistid facies will be necessary to define this boundary line pre- 
cisely ; but it is cited here as an illustration of the type of lithological vari- 
ations seen within the extent of the Texas Comanchean outcrops. For the 
other Washita formations likewise, much field work will be necessary to 
map even approximately their different lithological facies ; accordingly the 
following summary of these formations is brief and condensed. 


Sandstone facie*: 


Clay facie*: 

Upper half of the Del Rio Clay (approximately the Gryphea mucronata 
zone, south of the Brazos River). The middle member of the Grayson 
is a clay as far north as Denton County, Texas. 

Marl facie*: 

Near Bennington, Durant and Bokchito, Oklahoma, Denison, Fink, 
Gainesville, Denton, Fort Worth, and Burleson, Texas. This is the pre- 
vailing facies along the outcrop. The eastermost exposure in Central 
Texas is east of Roanoke, Texas, where the few, insignificant limy seams 
seen in the Fort Worth region are represented by eleven conspicuous 
limestone strata. There is little doubt that this formation grows rap- 
idly more calcareous eastward and southeastward, and that its limestone 
facies lies in this direction from the outcrop in North-Central Texas and 
not far from the outcrop. Passing down the Red River valley, however, 
this does not hold, for the formation is marly in the Tishomingo quadrangle 
and near Bennington, Oklahoma, where it has essentially the same lithology 
and fossils as in Tarrant County, Texas. 


In the Cerro de Muleros section, Bose's subdivision 8 1 consisting of 
yellow marls containing Schloenbachia sp., Pecten subalpinus (Bose), 
Exogyra whitneyi Bose, 2 Hemiaster calvini Clark, Protocardia texana 
(Conrad), and Enallaster bravoensis Bose, is Grayson. It overlies the 
Mainstreet formation, here a sandstone, and underlies subdivision 9, a 

'Bose: Inst. Geol. Mex. Bol. 25, p. 27-28. 
2 B6se: Univ. Texas Bull. 1902, p. 10. 

18 University of Texas Bulletin 

limestone which may be either Grayson or Buda, probably the latter ; this 
underlies the Woodbine (Dakota) sandstone. The Kent section contains 
equivalents of Weno and Pawpaw in division 3 of Durable and Cummins 1 
section, which however does not permit of more precise definition. 

A north-south line drawn two miles east of Roanoke, Denton County, 
therefore delimits the marl facies of the Grayson from the transitional beds 
to the limestone facies, since east of this line the Grayson becomes calca- 
reous. This line however probably turns east since on going down the Red 
River valley it leaves the marl facies of the Grayson to the north at seen at 
Denison, Bennington and numerous other places in Southern Oklahoma. 
What relations exist east and south of these points depends on well records 
not yet investigated. South of the Brazos River near Waco there is at the 
Grayson outcrop a transitional zone to the southern clay facies (zone of 
Gryphea mucronata, upper half of the Del Rio Clay) which continues west- 
ward to the El Paso region. The sand facies is unknown but is to be ex- 
pected in the removed areas of North Central Texas, in the isolated Upper 
Washita remnants of the Panhandle not yet investigated, and in the Tu- 
cumcari region. 

Limestone facies: 

The limestone facies, on the other hand, lying southwards in Sonora and 
Chihuahua is still unidentified in Texas, except at one point, the Mariscal 
Mountains, at the south tip of the Big Bend region. 2 

Sand facie*: 

At Cerro de Muleros, near El Paso, Texas ; apparently near Santa Rosa, 
New Mexico (Dr. Bb'se) . 

Clay facies (Del Dio Clay, in part) : The Del Rio Clay is poorly known, 
and therefore its correlation is tentative. It is equivalent to the Grayson 
and the upper part of the Mainstreet, and contains the following fossil 
levels : 

(1) Nodosaria texana Conrad. A zone of abundance above that of 
Exogyra cartledgei Bose 3 in the upper 30 feet of the formation, which at 
Shafter reaches a thickness of 190 feet. Below this zone of abundance 
Nodosaria is scattering. 

(2) Gryphea mucronata Gabb. Upper half of the Del Rio Clay. 

(3) Exogyra anetina Roemer. Rare near the middle of the clay in 

tumble and Cummins: Amer. Geol., xii, 1893, 309. 
2 Udden, Baker and Bose: Univ. Texas Bull. 44, 1919, p. 76. 
3 B6se, Univ, Texas Bull, 1902, 

Weno and Pawpaw Formations 19 

West Texas, abundant lower; in Central Texas (South Bosque, Round 
Rock, Austin) it is abundant in the basal half of the formation but rare or 
wanting above. It also occurs in the top of the Georgetown limestone at 

(4) Turrilites brazoensis Roemer occurs in the lowest five feet of the 
Del Rio Clay at South Bosque and at Austin ; its main zone of abundance is 
in the top of the underlying Georgetown limestone. 

Zones (1) and (2) are Grayson; zones (3) and (4) are Mainstreet; or 
briefly the upper part containing Gryphea mucronata is Grayson, and the 
lower part containing Exogyra arietina is Mainstreet. The Mainstreet 
equivalents locally have sandy levels in Central Texas, as for instance at 
the top of the Georgetown limestone at South Bosque and in the E. arietina 
slabs at Austin. Westward from the turning point of its outcrop in Bexar 
County the Del Rio becomes sandier and more flaggy and contains sandy 
slabs with Nodosaria and other fossils. At the south end of the Quitman 
Mountains the Del Rio is transitional, showing a mixture of sand and clay 
facies, and at Cerro de Muleros the Mainstreet, represented by Bose's sub- 
division 7 is sandstone. North of the turning point the typical Central 
Texas section continues to the Brazos, where the Del Rio differentiates into 
two portions by the intercalation of limestone strata basally; this basal 
part becomes upper Mainstreet and the upper marlier part becomes Gray- 
son. The lower Mainstreet however continues as a limestone into Central 
and West Texas. 

Marl facie*: 

The upper Mainstreet formation in McLennan County is transitional 
from clay to marl, and at South Bosque is rather calcareous. North of the 
Brazos this calcareous marl contains limy seams which become more prom- 
inent and take on the interbedded appearance of the Mainstreet limestone 
of North Texas. 

Limestone facie*: 

The typically developed Mainstreet limestone between the Brazos and 
the Red Rivers shows this lithological facies. There is considerable inter- 
bedded marl as far north as Gainesville. Eastward from Gainesville, down 
the Red River Valley, at Cedar Mills, Denison, Bennington, Bokchito and 
near Hugo, the marl is more reduced in amount, and the formation consists 
of compact, slightly marly, massive shell breccia or indurated limestone 
with typical Mainstreet fossils. 

20 University of Texas Bulletin 


The Pawpaw formation shows along its north-south outcrop an almost 
idealized sequence of marine facies. 

Sand facies: 

Red River Valley, as far south as the southern border of Cooke County, 

Clay faciet: 

Denton, Tarrant and Johnson counties, Texas, to near Riovista. 

Marl faciei: 

Johnson and Hill counties, Texas. 

Limestone facies: 

The equivalents of the Pawpaw south of the Brazos are questionable. 
If it is represented in this region, it is the upper part of the Georgetown 
limestone. (See page 11.) 

In West Texas its exact equivalent is unknown. At Cerro de Muleros 
however a distinct Weno and possibly Pawpaw fauna are present in Bose's 
subdivision 6, but not enough distinctive Pawpaw species are recorded to 
decide how much of this subdivision represents it. A hiatus at the base 
and at the top of the Pawpaw has been noted by Stephenson, 1 near the Red 
River, but it is unlikely that this accounts for any great thickness of Wash- 
ita sediments. 

Sand facies: 

There is sand in the upper half of the Weno, in the Red River Valley, 
Denison, Cedar Mills, Gainesville, Texas. In the lower half of the Weno : 
unknown. At Tucumcari, New Mexico, Dr. Bb'se found a sandstone, prob- 
ably Weno-Pawpaw, containing Ostrea quadriplicata Shumard, TurriteUa 
sp., Protocardia multistriata (Shumard), Protocardia sp. aff. texana 
(Conrad), Gryphea dilatata Marcou 2 and other fossils. 

Clay (shale) facies: 

Red River Valley, Gainesville and Denison, Texas. Contains a few thin 
ironstone seams; southward and to a less extent eastward this facies be- 
comes marly and is intercalated with thin limestone seams. 

Marl facies: 

Denton, Tarrant, Johnson and Hill counties, Texas. The upper half 
of the Weno is limy at places (as Fort Worth) where the lower half is 
marly. The formation is prevailingly of limestone throughout, south 

'Stephenson: U. S. G. S., Prof. Paper 120-H, p. 143. 

2 Marcou: Geology of North America, plate IV, figures 1, la, 3, 1842. 

Weno and Pawpaw Formations 21 

of the Brazos River. In West Texas at Cerro de Muleros, the Weno is rep- 
sented in Bose's subdivision 6, which consists of marls, sandstone and lime- 
stone. This series is therefore composite and transitional, like the Weno 
at Gainesville and Denison, and contains many identical fossils. 

Limestone facies: 

Portion of the Georgetown limestone near top, south of the Brazos. An 
indurated, massive limestone facies is unknown but probably lies to the 
east and south of the outcrop in Central Texas. 

Sand facie*: 


Clay facies: 

From Blue Mound, near Haslet, Tarrant County, Texas, northward to 
Denison. Contains pyrite and crustacean fauna. 

Marl facie*: 

In North-Central Texas along the outcrop the marl facies appears below 
Blue Mound, just north of Fort Worth and continues southward. In 
southern Oklahoma, the Red River Valley and Central Texas north of the 
Brazos, this formation is a clay, slightly arenaceous at the base and capped 
by shell conglomerate. This conglomerate is much more conspicuous at 
the Red River than at Fort Worth and southward, where it has largely 
disappeared, leaving a very shelly marl. South of the Brazos River, near 
Waco, there is a transitional zone between the marl and the limestone 


At Cerro de Muleros a portion of subdivision 5 is a gray marl containing 
great numbers of Gryphea washitaensis Hill, and represents the Denton. 

Limestone facie*: 

The portion of the Georgetown limestone which represents the Denton 
formation is a consolidated shelly limestone with very little calcareous 
cementing material, and usually massive without marl interbedding. It 
extends from a point near Waco southwards to the turning point of the 
Comanchean outcrops in Bexar County and thence westward to beyond 
the Pecos River. In the El Paso region, however, the equivalent to the 
Denton belongs to the northern (littoral-bathyal) facies and is marly as 
in North Texas. 


This formation is calcareous over all of North and Central Texas but is 
somewhat marly in the Red River valley and is prevailingly marly near El 

22 University of Texas Bulletin 

Paso. A line connecting these two areas will give very roughly the boun- 
dary between the marl and lime areas. 

Sand faciet: 


Clay facie*: 


Marl facie*: 

Cerro de Muleros, near El Paso, gray to bluish marls ; Denison and east- 
wards, marly limestone and marly interbedding. 

Limestone facie*: 

South of the Red River and throughout North and Central Texas at the 
outcrop. The middle portion of the Georgetown limestone represents this 
facies. A deeper sea subphase found in southern Trans-Pecos Texas con- 
sists of hard, crystalline, sparsely fossiliferous, relatively pure, fine grained 
lithographic limestone, which composes most of the Georgetown and Buda. 
This is the purest and probably the deepest sea deposition known for this 

Sand facies: 


Marl facie*: 

This group of strata is prevailingly a calcareous marl and contains the 
least limestone at Gainesville. At Fort Worth it has only slightly more 
lime than at Gainesville, while at Denison and at Caddo, Oklahoma, it is 
distinctly more limy. The change from marliness to liminess therefore 
appears to be in this region at least largely an east- west change. The 
Duck Creek marl thickens to the northwest, being thickest near Denison 
and thicker in the Tishomingo than in the Atoka area. 

Limestone facie*: 

South of the Brazos-Colorado River divide, the Duck Creek marl is im- 
bedded in the base of the Georgetown limestone, where it is a marly im- 
pure limestone. 

The situation in West Texas is unknown. 

Sand facies: 

Unknown. There are some bituminous sandy layers in the Duck Creek 
in Cooke County, Texas, but these appear to be local. 

Shale (clay) facie*: 

Seen at the type locality, three miles north of Denison, Texas. This 
shale is somewhat calcareous and is transitional to a marl. 

Weno and Pawpaw Formations 23 

Marl facie* : 

This facies invades the limestone series at Gainesville, Texas, where 
all of the lower Duck Creek except the basal ten feet is prevailingly marly. 
Probably the removed portion of the Duck Creek west and north of the 
outcrop was prevailingly marly. 

Limestone facie*: 

Extends from Denton County southward to the turning point of the 
Comanchean outcrop in Bexar County, and thence westward to the Trans- 
Pecos region. The group of strata is composite and at a given point is 
more marly above than below. For instance, at Denison the Hamites and 
Desmoceras zones are prevailingly limy marl with some blue shale, and at 
Denison the zone of Desmoceras brazoense is marly at the top; at Fort 
Worth the section is limestone to the top of the Schloenbachia trinodosa 
horizon and limy even above this ; while below the Brazos the whole lower 
Duck Creek section becomes limy. 

South of the Brazos the Duck Creek formation lies at the base of the 
Georgetown limestone where it is a chalky white indurated rather un- 
fossiliferous limestone, differing considerably in appearance at Austin 
and at Georgetown, Texas; while west of the southern turning point of 
the outcrop it becomes a hard, crystalline, consolidated, sparsely fossilifer- 
ous limestone. At Cerro de Muleros near El Paso, on the contrary, the 
northern littoral facies is present as at Gainesville and Denison and this 
level is represented by a series of clay, marl and limestone, which repre- 
sents a transitional facies. Vraconian faunae from Chihuahua and Zaca- 
tecas (p. 60) represent in part this stratigraphic level. 

Sand facie*: 


Clay (abate) facie*: 

From near Primrose, southwestern Tarrant County, south througn 
Johnson County to beyond the Brazos. This formation at Blum, Hill 
County, is a yellowish clay 19 feet thick. This facies contains a con- 
spicuous limonite fauna, Schloenbachia, Area, small gastropods and pelecy- 
pods and other fossils. 

Marl facie*: 

Southern Tarrant County to between Gainesville and Fink. The forma- 
tion is increasing in thickness northwards and as the clay facies disap- 
pears, flag layers enter first as limestone in thin sheets and farther north 
as shell conglomerate sheets. The bulk of the formation is marl, and the 
limonite fauna has largely disappeared. 

24 University of Texas Bulletin 

Lime facies (conglomerate): 

Fink, Grayson County, Texas, to east of Hugo, Oklahoma. Coincident- 
ally on passing eastwards and northwards from the marl facies the scat- 
tered shells in the formation become consolidated into conglomeratic sheets 
with shelly marl between, and these predominate at Gainesville and Deni- 
son. Turning east down the Red River Valley the thickness of the Kia- 
mitia and the amount of this conglomerate greatly increase. Near Hugo, 
Oklahoma, the Kiamitia shell conglomerate is about 150 feet thick and is 
extensively used for crushed rock. This formation is a shallow water 
oyster bed deposit of mixed Fredericksburg and Washita fossils, mainly 
the former. 

The formation disappears at the Brazos-Colorado uplift, and in West 
Texas its relations are unknown. 


The Fredericksburg Division also must be considered sectionally, since 
its various parts behave differently as to their changes of thickness and 

Sand facies: 


Clay facies: 


Marl facies: 

Unknown. Bose's subdivision 3 at Cerro de Muleros contains some 
marl, but this subdivision is not positively known to be Edwards. Through- 
out the Red River region and North-Central Texas, the top of the Good- 
land, which is thought to correspond to the Edwards, is a non-marly lime- 
stone, usually massive and sometimes crystalline. North of Sheffield and 
Fort Stockton, the Fredericksburg is stated to be prevailingly marly. 

Limestone facies: 

This is known from Fort Worth south to the turning point of the out- 
crop in Bexar County, and thence west to El Paso. The Red River ex- 
tension of this level is not identifiable with certainty because it is not 
clear whether the 12-20 feet of white limestone at the top of the Fredericks- 
burg division as seen at Denison or north of Goodland, Oklahoma, repre- 
sents only the Edwards or also in part still lower Fredericksburg. The 
Edwards is less than 10 feet thick at Fort Worth; it is 33 feet thick at 
Comanche Peak, and southwards thickens rapidly. 

Rudistid facies: 

The Rudistids invaded Texas most widely in upper Fredericksburg time, 
when they were scattered as far north as Fort Worth ; however, they are 
very rare and inconspicuous north of the Brazos, in Central Texas. In 

Weno and Pawpaw Formations 25 

West Texas they are reported as far north as Bailey County, and they 
are common in Coke and Runnels counties. In Trans-Pecos Texas, the 
Texas and Pacific Railway roughly divides the southern rudistid facies 
of the Edwards from the northern littoral facies. The rudistids are 
rare or wanting at Cerro de Muleros, Kent, Sierra Blanca and the Finlay 
Mountains ; and present at points between these and the Rio Grande. Gabb 1 
describes from the Sierra de las Conchas near Arivechi, Sonora, fossils 
which if correctly identified include among diverse stratigraphic levels 
that of the Edwards limestone ; the facies represented is unknown to me. 
Felix and Lenk'- also record the great extent of the Fredericksburg reef 
facies in Mexico. 


The influence of the underlying syncline on the deposition of these two 
upper Washita formations is small, due to their small thickness. However, 
they show an appreciable syncline in the Fort Worth region, and a con- 
spicuous thinning southward. 

Since the maximum rate of change of thickness, like the maximum 
change in lithology, may not coincide in direction with the outcrop, the 
formation along the outcrop will in general show only a greater or less 
north-south or an east-west component of change in thickness or lithology 
and the maximum change will be in a direction lying at an angle to the 

North-South Changes 

This is true of the north-south outcrop of the two formations, which 
does not exactly coincide with the direction of greatest thickness change. 
The Weno and Pawpaw strata outcrop in a line passing about a mile east 
of Gainesville, Cooke County, and thence nearly south to near Denton; 
thereafter the boundary between the two formations runs near Fort Worth, 
west of Cleburne, Riovista and Blum. 

The outcrop thus from the Red River to the Brazos has a general trend 
of east of north, while the direction of greatest thickness change is slightly 
east of north. (See figure 3). 

'Gabb: Pal. Cal., vol. 2, p. 257 ff. 

2 Pelix and Lenk: Beitr. z. Geol. u. Pal. d. Rep. Mex., II, p. 28. 

26 University of Texas Bulletin 

East-West Changes (North Texas and Oklahoma) 

In the whole Red River region these two formations at their outcrops 
maintain an almost uniform thickness, but they are slightly thicker east- 
ward as far as Choctaw County, Oklahoma. Their behavior east of this 
point is unknown to me. 



Weno Paw- 
Locality Lower Upper Total paw 

Denison 45 80 125 60 

Gainesville 40 70 110 44.8 

Blue Mound (Haslet) 27.3 

Fort Worth 12.7 49.6 62.3 24.6 

Riovista '. 10 25 35 5.0 


The Weno and Pawpaw formations are marked by striking lithological 
changes which produce along their outcrops localized lithological regions 
each with a characteristic fauna. The Pawpaw formation, and to a less 
extent the Weno, passes from north to south along its outcrop through a 
"typical" series of lithological fades sand-clay-marl-limestone, which 
aside from various complicating factors of deposition is usually taken to 
represent a progressive series of marine facies from near-shore .to off- 
shore conditions. Likewise the problem of localized faunales is vividly 
impressed upon one by the situation in the Pawpaw clay (as also in the 
Weno), where within a few miles one fauna largely disappears and an 
equally rich and varied, but different one occupies its stratigraphic posi- 
tion. For example the Gainesville-Denison fauna (Nacreous, Area), the 
Fort Worth fauna (Turrilites, Engonoceras, Hamites, Scaphites) and the 
Riovista fauna (Flickia, echinoids) of the Pawpaw formation represent 
three different marine facies. The narrow ribbon-like outcrop of these 
formations in North Central Texas and Southern Oklahoma gives only a 
limited opportunity for the study of these different marine phases, but the 
following regional differences in the sediments of these formations are ap- 

Weno and Pawpaw Formations 

Nature of Material Locality of Outcrop 


(a) Semi-consolidated sandstone and 


Choctaw county, Oklahoma 
Marshall county, Oklahoma 
Bryan county, Oklahoma 
Love county, Oklahoma 
Grayson county, Texas 
Cooke county, Texas 

of Marine 

(b) Clay with sandy layers f Denton count y 

| Tarrant county 

(c) Marl with limy layers. . . f Johnson count y 

{ Hill county 

(d) Limestone South of Brazos River 



Deeper Sea 




stone | Cooke county Neritic 

Marl with lime layers Denton county Bathyal 

Limestone Tarrant county and south wardDeeper Sea 

(in part Zoogenic) 

(a) Shale with sand layers Red River region Neritic 

(b) Marl and limestone layers Cooke county to Brazos RiverBathyal 

(c) Limestone South of Brazos River Deeper Sea 


Eastward from the turning point of the Comanchean outcrops in the 
Red River uplifted area near Orlena, Cooke County, Texas, the Pawpaw is 
a ferruginous sandstone or an unconsolidated sand. This outcrop runs 
down the Red River valley in a direction a little south of east, lying in 
Cooke and Grayson Counties, Texas, and in Love, Marshall, Bryan, and 
Choctaw Counties, Oklahoma. 

Sandstone Facies 

(a) (Semi-consolidated Sandstone and Ironstone) 

In general, the Pawpaw formation is prevailingly sandy and iron bear- 
ing at its outcrops north and east of the south border of Cooke County, 

28 University of Texas Bulletin 

Near Gainesville, the formation is a series of thickbedded, hard, ferru- 
ginous sandstones with interbedded, laminated impregnated sandy layers 
and semi-consolidated iron-impregnated sand. The layers are locally a 
shell conglomerate containing great quantities of casts of Area, Turritella 
and other bivalves and gastropods. The basal layers are characterized by 
an abundant pyrite fauna. Turrilites, Scaphites, Hamites and echinoids 
are rare or absent. This type of lithology continues around the turning 
point of the Comanchean formations south of Orlena to a point near Potts- 
boro; and at Denison the Pawpaw formation is almost entirely a coarse 
consolidated brownish-red sand with few fossils. At Durant the formation 
is similar to the Denison exposures. Eastward through Bennington and 
Bokchito the sandy phase continues, and is included in the Bokchito for- 
mation of Taff. 

Section 22, R. 12 E., T. 5 S. (furnished by W. M. Winton) 


Limestone, iron stained, old cap of hill, practically removed by weathering. 


Massive yellow red sandstone, soft in fresh exposures, indurated where long 

exposed ; no fossils seen 5.0 

Soft limonitic sand ; no fossils seen 30 . 

Ironstone ledge composed of fossils (Area sp., Ostrea quadriplicata, small 

ammonites, gastropods, etc., a typical Pawpaw fauna) 0.5 

Red sand, cross bedded and containing lenticular hard masses of sandstone 10.0 
Ironstone ledge composed of fossils (Area sp., Ostrea quadriplicata, am- 
monites, Nodosaria, etc., a typical Pawpaw fauna) 0.8 

Red sand 10.0 


Yellowish hard limestone with typical Weno fossils 0.8 

Soft marl ; no fossils seen 0.3 

Very hard massive limestone, pinkish in color. Large numbers of fossils 
having same hardness as matrix and giving uniform fracture. Ledge 
forms conspicuous topographic break traceable for miles. Schloenbachia 

sp. M., and other typical Weno fossils 1.9 

Soft marl 15.0 

Limestone ledge sandy; no fossils seen 1.0 

Soft marl with a few thin limestone ledges, each less than 0.5 feet thick 95.0 


Conglomerate of Gryphea washitaensis, Ostrea carinata, and other Denton 
fossils. Typical Denton marl ("Caddo" limestone of Taff, top). Ex- 
posed, about < 2.0 

Weno and Pawpaw Formations 29 

In the creek, one-fourth mile west of the mountain, the contact between the Duck 
Creek marl and the Fort Worth limestone is exposed as at Caddo, Oklahoma. 

In the second cut 1V miles north of Hugo, Oklahoma, there is 10 inches 
of shell conglomerate containing abundant juvenile and adult Ostrea 
quadriplicata Shumard, Gryphea washitaensis Hill, Plicatula sp., Pecten 
subalpinus (Bose), abundant Leiocidaris spines, Corbula littoralis Adkins, 
and other typical upper Weno fossils as found at Gainesville and Denison. 
This represents part of the Quarry limestone group. Above it is an iron- 
stone ledge, 4 inches thick, which is red-stained and conglomeratic and re- 
sembles the basal Pawpaw as seen at Gainesville. 

Along the St. Louis and San Francisco Railway track between Benning- 
ton and Bokchito, Oklahoma, the upper Washita section, Woodbine to 
Weno, is seen to advantage. The Grayson marl with an estimated thick- 
ness of 50 feet is well developed with its characteristic fossils. 1 

The Mainstreet limestone is seen in roadside cuts one mile northwest of 
Bennington, in the caprock of Sugarloaf Mountain, six miles north of Ben- 
nington, in the bed of Sulphur Creek, where it forms an extensive pave- 
ment limestone, and in the railroad cuts nearby, particularly in the long 
cut running west down to Bokchito Creek, which has it well exposed. 
Everywhere it is underlain by the brown consolidated Pawpaw sandstone. 
The nature of the Pawpaw and Weno outcrops in this region is seen from 
the following section. 



Brown limestone with Turrilites brazoensis, Pecten subalpinus, Exogyra sp. 
(large), and ammonites. The top of the exposure is an Exogyra 

arietina conglomerate. Exposed 2 

Brown-blue limestone with irregular sandy inclusions 1 

Yellow limestone containing Kingena wacoensis, Ostrea marcoui, and Pecten 

subalpinus 1 . B 

'Taff (U. S. G. S. Geologic Atlas of the United States, Atoka Folio, No. 79) has 
overlooked the Grayson marl, which in this quadrangle is typically developed as at 
Denison. It may be seen near the Woodbine ("Silo") sandstone knob mapped by Tafl 
one mile northwest of Bennington, Oklahoma, where it overlies typical Mainstreet 
limestone containing Turrilites brazoensis Roemer, Exogyra arietina Roemer and othei 
distinctive fossils, and contains Gryphea mucronata Gabb, Gryphea, sp. (truncate) 
Pecten subalpimts (Bose), Plicatula sp., Ostrea sp. aff. subovafa. Shumard, and 
Kngonoceras sp. This locality is mentioned by Taff, ibid., p. 6. It also forms the 
overburden in the Mainstreet quarry one mile north of Durant, Oklahoma, where it 
is very fossiliferous. 

30 University of Texas Bulletin 


Consolidated brown sandstone, no fossils seen 5 

Unconsolidated sand, iron stained 10 

Blue jointed clay with scattered Gryphea 10 

!<ed-brown sandstone calcareous in part with nacreous and ironstone fos- 
sils: Area, Nucula sp., Corbula sp., Cerithium, Turritella, Anchura, 

like the Gainesville and Denison nacreous fauna 1 

Marl, containing ironstone seams, no fossils seen 10 

The cut east of the Bokchito Creek bridge shows the foregoing section 
much better exposed. Pawpaw exposures were also noted near Durant, 
Oklahoma. North of the railroad, 11/2 miles east of Bennington, Oklahoma, 
about 50 feet of massive brown sandstone was noted underlying the Main- 
street limestone at the top of the hill. This sandstone contains limy layers 
bearing Ostrea quadriplicata, 0. subovata(l), marcoui, Trigonia sp., Gry- 
phea sp., and Pecten sp. (large). Taff gives the following section for his 
Bokchito formation in the Atoka and Tishomingo quadrangles 1 : 



J. A. Taff, 1902-1903 


4. Sandy and clay shales, and locally friable, cross bedded sandstone. In the 
clay and in some of the iron and lime concretions, shells are preserved 
with original nacre 50 

3. Hard, semi-crystalline, bluish, oyster shell limestone, weathering yellowish 

and projecting as ledges separated by friable shales 10-20 

- 2. Friable sandstone beds, locally cross bedded, alternating with and including 

deposits of sandy clay 20-3C 

1. Sandy clay shale, with ferruginous limestone segregations and ironstone 

nodules 90 


This thickness is given as 140 feet in the texts and the Columnar Section sheets of 
both folios. 

The upper member (4) of this section is probably Pawpaw. Sheets of 
nacreous shells in the Pawpaw have been noted in Grayson County. The 
other three members are Weno. 

The Pawpaw formation is exposed in the hilltops east of Denison and 

iTaff: U. S. G. S., Geologic Atlas of the United States, Atoka Folio No. 79, 1902. 
p. 6; and, Tishomingo Folio, No. 98, 1903, p. 6. 

Weno and Pawpaw Formations 31 

may be seen in cuts on East Main Street, where it is a cross-bedded rather 
consolidated, brick red sandstone. No fossils were seen at this locality. 
The formation is stated by Stephenson 1 to be 50 or more feet thick near 
Denison. The Pawpaw is poorly exposed north of a west branch of Little 
Mineral Creek just south of Fink, where it is steeply tilted. On the Red 
River about 2 miles northwest of Cedar Mills, Grayson County, there is a 
long cliff dipping west (5) which exposes near the top about 40 feet of 
loose sand only partially consolidated, which is probably Pawpaw. 




White limestone with Ostrea quadriplicata, Turrilites brazoensis, Kingena, 
Exogyra arietina, Pecten subalpinus, Enallaster sp. aff. texanus. Seen 
in ravine above east end of river bluff near road 10 


Sandstone with thin ferruginous layers 40 

Blue marl with clay and sand seams and nacreous fossils: Engonoceras, 

Corbula, Nucula, Ostrea quadriplicata, Pecten subalpinus 30 


Massive grayish semi-crystalline limestone 2 


Blue marl with nacreous fossils 40 

The roadside cuts 2i/ 2 miles east of Gainesville, Cooke County, inconsec- 
utive sections of the Pawpaw are seen. The interval from the top of the 
Quarry group to the base of the Mainstreet limestone is not less than 45 
feet. The base of the Pawpaw overlying the Quarry limestone is seen in a 
cut of the Missouri, Kansas and Texas railway (Wichita Falls branch) at 
the north end of the brickyards pit 1% miles southeast of Gainesville. 
This exposes about 8 inches of an irregularly deposited reddish ferrugin- 
ous shell conglomerate largely of Ostrea quadriplicata cemented into the 
pitted surface of the Quarry limestone. The same level is exposed near 
the water tank on the southwest rim of the pit. In roadside cuts % mile 
southeast of this locality about 45 feet of Pawpaw may be seen poorly ex- 
posed ; it consists of thin layers of ferruginous dark red brown sandstone 
which, locally at least, consists of cemented masses of ironstone fossil casts : 
Area, Protocardia, Nucula, Corbula, Turritella and rare Ostrea quadripli- 
cata and Gryphea. These ironstone layers are interbedded with brown to 

iStephenson, U. S. G. S., Prof. Paper 120-H, p. 142. 

32 University of Texas Bulletin 

yellow, softer, ferruginous, very arenaceous clay. Their ironstone seams 
do not exceed 6 inches in thickness and locally are highly indurated. 



^Section furnished by W. M. Winton 


White massive limestone with characteristic Mainstreet fossils. Exposed ... 6 


Alternating red ironstone and ferruginous sandy clay layers. About 16 
compact ironstone layers each 3 to 4 inches thick, alternating with clay 
layers each about one foot thick. The ironstone layers are similar from 
bottom to top and the basal 10 feet is more fossiliferous than the upper 
portion. The ironstone layers contain: Remondia sp., Trigonia sp., 
Area sp., Engonoceras sp., Nucula sp., Corbula sp., and other nacreous 

and ironstone fossils 21 . 5 

Brown sandstone flag layer 0.5 

Red ironstone layer with Nodosaria texana . 

Brown clay 5 . C 

Red ironstone with Area sp., Ostrea quadriplicata O.B 

Brown clay, sparsely fossiliferous : Area, gastropods 15 . C 

Red calcareous sandstone: Ostrea quadriplicata 2.C 

This is underlain 'by the Quarry Limestone group (see page 36). The 
thick semi-consolidated sand seen in Grayson County is absent. The Paw- 
paw outcrop which has turned nearly south at the turning point near Or- 
lena, makes a narrow north-south strip from Gainesville to the southern 
border of Tarrant County. The ironstone facies does not persist past 
the Trinity River, since interstratified clay lenses here largely make up the 
formation ; as far south as Fort Worth there are large amounts of weath- 
ered ironstone fragments in the surface debris of the Pawpaw. 1 

Clay Facie* 

This facies of the Pawpaw formation is best developed in the Fort Worth 
region. From Cooke County southward to the Brazos the Pawpaw is rap- 
idly thinning, as previously described. At the same time, passing south- 
ward through Denton and Tarrant Counties the clay facies is encountered, 
and in the region of the Brazos the marl facies appears. The clay facies 
grades into each of the other two facies, so that the transitions are gradual. 
This gradation occurs through the invasion of one facies by seams of the 
other kind of material. 

'Winton and Adkins: Univ. Texas Bull. 1931, p. 67. 

Weno and Pawpaw Formation? 33 

The transitional zone from the ironstone to the clay facies occurs in Den- 
ton and northern Tarrant Counties. As far south as the Trinity River con- 
siderable amounts of ironstone fragments occur in the Pawpaw exposures ; 
these are the residue of numerous thin ironstone ledges similar to those of 
the Red River area but sparsely fossiliferous, which are scattered rather 
evenly throughout the formation. The interbedding material is an arena- 
ceous clay. South of the Trinity the section is prevailingly clay but has 
thin ironstone, limestone and sand seams. 



White chalky limestone, exposed 4 


Brown to yellow, sparsely fossiliferous clay, with thin ironstone seams and 

scattered sand lenses 23 

Sandstone flag layer 0.3 

Brownish yellow impure clay 4 

Thickness of Pawpaw 27 . 3 

On Sycamore Creek, three miles southeast of Fort Worth the Pawpaw has an average 
thickness from several measurements of 7.5 meters (24.6 feet). 

At the southern border of Tarrant County the Pawpaw 'is 12 feet thick 
and is transitional to the marl facies. In northern Johnson County the 
transitional zone continues and the section consists of clay mixed with 
marl. Passing from the upper Noland's River southeast to Riovista the 
section changes considerably, for from Riovista southward the marl facies 
is found, with little clay and no ironstone; there is also a corresponding 
change in the Pawpaw fauna. 



Section furnished by W. M. Winton 


Massive limestone containing Pachymya sp., Turrilites brazoensis, Holectypus 

limitis, Pecten sp 32 . 4 


Reddish clay containing fragments of Turrilites sp., Area sp., etc.. pyritized 10.8 


Limy marl capped by a hard lime ledge one foot thick, containing Pecten 

georgetownensis, Nautilus texanus, Pinna sp., Kingena sp 7.8 

34 University of Texas Bulletin 

Marl, containing Nodosaria texana 1.0 

Massive limestone containing Schloenbachia sp. M. (notched tubercles), 
Nautilus texanus, Epiaster sp., Protocardia sp., Gervilliopsis invaginata 

(one) * 7-4 


Soft whitish marl, no fossils seen 10.0 

Marl Facies 

The transition from clay facies to the marl facies of this formation takes 
place rather abruptly, within a distance of 2 miles along the outcrop and 
terminates in central Johnson County, south of which the formation is al- 
most entirely marly. One mile southeast of Riovista, the Pawpaw is a dis- 
tinctly marly uniform light yellow, fossiliferous deposit lying between the 
conspicuous Weno and Mainstreet limestones. It is about 5 feet thick. In 
the territory covered by this depositional phase the conspicuous pyrite fauna 
of the Fort Worth region is rare, except a few Turrilites, Area and small 
gastropods, and other fossils, echinoids and ammonites are abundant. 



Massive white limestone with characteristic Mainstreet fossils: Turrilites 

brazoensis, Kingena, Exogyra, arietina. Exposed 5 


Homogeneous calcareous, straw-yellow marl with a few ironstone and calca- 
reous fragments, containing Enallaster bravoensis, E. wenoensis, E. 
riovistae, Holaster sp., Epiaster wenoensis, Plicatula sp., *Flickia boesei, 
'Schloenbachia, sp., *Turrilites sp., *Arca washitaensis 5.5 


Limestone escarpment in two terraces, poorly exposed at the base, consisting 
of massive soft limestone with marl interbedding. Contains Enallaster, 
Epiaster, Holaster, Hemiaster calvini, Pecten subalpinus, Plicatula and 
many other fossils, Trigonia clavigera. About 40 


Soft light straw-colored marl containing Gryphea washitaensis, Ostrea cari- 

nata, Pecten subalpinus, Plicatula sp., and Kingena sp. (large) 5 

LIMESTONE FACIES : The equivalents if any of the Pawpaw forma- 
tion in Central Texas are largely insignificant since they consist of only a 
minute thickness of very calcareous marl and limestone imbedded in the top 
of the Georgetown limestone, underneath the Turrilites brazoensis zone 
which represents the basal Mainstreet formation of North Texas. This sit- 
uation presumably exists westward to the Trans -Pecos region wherever the 

Weno and Pawpaw Formations 35 

more southward section is found. However, in, West Texas, on passing 
northward into the near-shore facies (as at Kent and Cerro de Muleros) 
the Weno and Pawpaw formations again thicken, as in passing from Austin 
to Fort Worth, and show characteristic and so far as can be judged from 
published accounts .similar fossils. This level at Muleros has echinoids and 
ammonites and other distinctive fossils (see page 41), but so far the large 
pyrite fauna of the North Texas Pawpaw has not been reported from West 


A summary of the marine facies of the Weno formation and several ge- 
ological sections have already been given. The Weno formation is compos- 
ite, and represents different phases of marine deposition both at different 
places and in its different levels at the same place. In the Red River region 
the formation is mostly a series of blue shales with clay-ironstone, lime- 
tone and irregular consolidated sand seams. The ironstone and shale lay- 
ers are rich in nacreous fossils. The shale is here capped by the Quarry 
limestone group, which loses its massive character south of Denton County, 
Passing southward from the Red River, the basal Weno transforms from a 
clay into a calcareous marl with shelly, often slabby, limestone seams and 
the upper part after passing rapidly through a marl stage becomes pre- 
vailingly a soft chalky fossiliferous limestone. This is the situation in Den- 
ton and Tarrant Counties. The basal division is also capped by a thin 
chalky limestone which forms a bench, and the Weno thus consists of two 
terraces, a persistent topographic feature which passes southwards across 
Denton, Tarrant, Johnson and Hill Counties and disappears only in north- 
western McLennan County where the Weno limestone consolidates with 
the Mainstreet and Fort Worth limestones (by the virtual disappearance of 
the intervening softer formations) to form the middle Georgetown lime- 

In the Red River region the shale (clay) facies predominates from south- 
ern Cooke County to east of Bennington, Oklahoma. It is conspicuous in the 
first deep cut of the St. Louis and San Francisco Railway track north of 
Denison, of which a photograph is given by Stephenson, 1 and in the pit of 
the brickyard 1% miles southeast of Gainesville ,of which a section is here 

'Stephenson, U. S. G. S., Prof. Paper 120-H, pi. XXII B. 

36 University of Texas Bulletin 



Shell limestone, consisting almost entirely of masses of comminuted shells. . . 0.2 
Shelly calcareous marl, with ironstained arenaceous cement and masses of 


This stratum contains: O. quadriplicata, Pecten subalpinus, Plicatula 
sp., Leiocidaris sp. spines. 

Hard reddish limestone composed almost entirely of- comminuted shells iron- 
stained 3 

Shell conglomerate of small packed shells, laminated .5 


Compact shelly blue to yellow limestone containing many comminuted shell 

fragments. QUARRY LIMESTONE 9 

This stratum contains: Gryphea sp., Pecten subalpinus, cidarid spines 
(rare), Plicatula sp. 

Shell conglomerate of Gryphea washitaensis chiefly, with considerable cal- 
careous cement. GRYPHEA CONGLOMERATE 7 

This stratum, which is conspicuous as just underlying the cap rock 
of the rim of the pit, contains: Ostrea carinata, cidarid spines, Ostrea 
marcoui, Plicatula sp. 


Packed bluish to yellow clay, with two thin seams of Gryphea shell conglom- 
erate, each one inch thick 1.0 

Sand layer containing no fossils, irregular thickness, about .2 

Blue to yellow shale, with a considerable amount of sand in the form of 

irregular anastomosing sand lenses and streaks. Fossils in the shale . . 4.7 

Ironstone band .1 

Blue to yellowish iron stained shale, with irregular calcareous concretions, 

locally called "ginger shale" 2.5 

The ginger concretions also occur in the sandy layer just above the 
ironstone seam. 

Fossiliferous Ironstone stratum .5 

The clay-ironstone of this and the overlying ironstone layers has been 
excavated and dumped in a large heap on the east rim of the pit. 
Material in situ in the pit and that in this heap bears the following 
nacreous fossils: %Protocardia sp. aff. multistriata (Shumard), very 
abundant as casts and molds, with the original shell; $Barbatia sp., 
JCorftwto basiniformis Adkins, $Nucula nokonis Adkins, %-Nucula weno- 
ensis Adkins, $Globiconcha sp., ^.Natica sp., \Cinulia washitaensis 
Adkins, Cambarus (?) sp., %Schloenbachia wintoni Adkins, %Gervilliopsis 
invaginata (White), %Pecten inconspicuus Cragin, $An,chura mudgeana 
(White), and many other fossils. 

Blue fossiliferous shale and calcareous bands 4.0 

This material is an alternation of thin bands of yellow sandy lime- 

Weno and Pawpaw Formations 37 

stone with packed laminated blue-gray shale, slate color when fresh, 
but weathering to blackish-blue. 

Fossiliferous ironstone band .2 

Blue shale, laminated, jointed on weathering, very fossiliferous 19.8 

This layer contains an abundant nacreous shell fauna, including: 
Gervilliopsis invaginata (White), Gryphea washitaensis Hill (juvenile 
stages), Enallaster sp., Tellina sp., Corbula basiniformis Adkins, Nucula 
wenoensis Adkins, Pecten inconspicuus Cragin, Anchura mudgeana 
White, Natica sp., Turritella sp., Cerithium sp., etc. 
Gray-blue arenaceous laminated shale, calcareous in part, forming a terrace 

in the pit. G. washitaensis, Gervilliopsis invaginata, Pecten, Plicatula .3 

Laminated blue shale '. .2 

Ironstone seam .1 

Laminated gray-blue shale 1.9 

This works down into kidney-shaped lumps, and is locally called 
"kidney shale." 

Arenaceous laminated marl. Gryphea washitaensis abundant at top and 
bottom. Main zone of Gervilliopsis invaginata (White), Trigonia clav- 
igera Cragin, Pecten subalpinus Bose, Leiocidaris spines. This layer 

forms a secondary terrace .8 

Blue fossiliferous marl. Locally called "buff marl," a desirable brick ma- 
terial, free from impurities, burns to buff color 11.2 

51. C 

This material has been thrown in heaps onto the terrace above and is rich in small 
calcitic fossils, including: Venericardia wenoensis Adkins, Trochus laticonicus Adkins, 
Trigonia clavigera Cragin, Neritina, Nerita, Pecten sp., worm tubes, minute corals 

In the bottom of the pit covered by water is about 30 feet more of Weno shale. 
It is stated that the pit has at one point been dug 70 feet deep. A water well 
nearby passed through the Denton marl into the Fort Worth limestone. The Dentor, 
marl is poorly exposed one-fourth mile west of the pit, and the Fort Worth limestone 
is finely exposed with its typical sequence of fossil zones, in the creeks between th( 
brickyard and Gainesville. 

The Quarry limestone is variable in thickness. Blocks two to three feet 
thick have been excavated from the pit and thrown in a heap above its 
south rim. An extensive outcrop, with quarried indurated blocks, three 
feet thick, occurs three miles east of Gainesville just north of the track. 
The quarry group forms a persistent outcrop eastward to the river near the 
the northeast corner of Graysoh County, in which county its relations 
have been described by Stephenson. In Denton County on the Denton- 
Krum road, it outcrops as a bench, and is 15 inches thick. Here it is 
abundantly fossiliferous, and contains Pecten subalpinus, cidarid spines, 
Ostrea marcoui, Gryphea washitaensis and Ostrea carinata. Beneath it 
is a ferruginous and calcareous shell conglomerate layer 1 to 2 inches 
thick consisting almost entirely of the last two species named. In Tarrant 

38 University of Texas Bulletin 

County it is consolidated with the top of the Weno formation, which is a 
chalky limestone. 



White massive limestone, with Kingena wacoensis (?) (Roemer), Turrilites 
brazoensis Roemer, Exogyra arietina Roemer, Pecten subalpinus (Bose), 
Homomya, Pachymya, Ostrea carinata (?) Lamarck. Exposed 15.0 


Marl and clay, with thin ironstone seams. The top marly portion contains 
Enallaster sp., Hemiaster sp., Holaster sp., Epiaster sp., Pecten sub- 
alpinus (Bose) and many other calcite fossils 18.0 

Sandstone flag layer. STARFISH ZONE 3 

Ironstained reddish impure clay with many pyrite fossils, including : Engon- 
oceras sp., Turrilites sp., Hamites tenawa Adkins and Winton, Holaster 
sp., Enallaster sp., Hemiaster sp. aff. bexari Clark, Acanthoceras 
worthense Adkins, Area, sp., Nucula sp., Mortoniceras worthense Adkins, 
Schloenbachia sp 4.0 


Impure limestone, forms top of first terrace. Marlier beneath, Nodosaria 

texana Conrad, zone at the base 19.7 

Limestone at top, forming second terrace, marl beneath. Contains a large 

fauna, rich in echinoids and pelecypods. . . . 31 . 

Limestone ledge, indurated, fucoidal, Gervilliopsis invaginata (White) zone, 
Gryphea washitaensis Hill, Pecten subalpinus (Bose), Pinna guada- 

I it par Bose 1.3 

There is about 13 feet of fossiliferous Weno marl beneath the creek bed. This is 
well exposed at the locality 618 (q. v.). 






White massive, in part marly, limestone, with Kingena (?) wacoensis 
(Roemer), Exogyra arietina Roemer, Turrilites brazoensis Roemer, 
Ostrea carinata Lamarck (?) 6.0 


Brown clay, marlier ot the top, with an abundant pyrite fauna at the base, 
including: Area sp., Mortoniceras worthense Adkins, Acanthoceras 
worthense Adkins, Engonoceras sp., Schloenbachia sp., Hamites sp., 
Turrilites sp., Plicatula sp., Pecten subalpinus (Bose), Enallaster bravo- 
ensis Bose, E. wenoensis Adkins, Epiaster wenoensis Adkins, and other 
species 20.7 

Weno and Pawpaw Formations 39 


Chalky limestone; contains: Ostrea sp. aff. diluviana, Ostrea curinata (?) 
Lamarck, Pachymya austinensis Shumard, Homomya sp., Schloenbachia 
sp. (M.), Pecten subalpinus (Bose), Pecten texanus Roemer, Plicatula 

sp., Nodosaria texana Conrad, and many other species 13.5 

Yellow marl with many limestone bands, poorly exposed 36.2 

Hard white limestone, fucoid, with Gervilliopsis invaginata .5 

Brownish yellow marl, about ' 15.0 




Section furnished by Gayle Scott 

Section is from creek bed to upland; direction of section, 92 degrees from magnetic 


Weathered limestone : 15.6 

Limestone ledge, with slight terrace above 2.7 


Terrace, covered with soil and water-soaked, marl base; contains a sandstone 

ledge two feet below top - 10.4 

Red, ironstained, slightly sandy marl, with numerous small pyrite fossils; 

characteristic weathering of receding Pawpaw hillsides 12.0 

Yellow marl, in part soil-covered overlying the flat narrow terrace formed 

by top member of Weno limestone L : 3.0 


Hard limestone ledge, partly concealed, about 3.2 

Disintegrated thin limestone ledges alternating with marl layers of varying 

thickness, partly concealed by limestone debris and soil 10.5 

Limestone ledge, impure, yellow, heavily ironstained, indurated ledge, con- 
taining Pentagonaster texensis Adkins and Winton (rare), and small 
starfish, indet. (fairly numerous). This ledge forms the base of the 
abrupt upper Weno terrace, and is easily recognizable in the Fort Worth 

Yellow marl, heavily ironstained, containing thin limestone ledges. NODO- 

Disintegrated limestone, capped by a thin limestone ledge 3.2 

CONCEALED. Interval contains Gervilliopsis Zone 28 . 5 

Heavy limestone ledge, impure, fucoidal, yellow, and slightly less resistant 

than the one mentioned below .9 

Blue marl (pipe clay), weathering to gray, fractures on drying into small 

blocks 3.5 

Heavy limestone ledge, fairly pure, very resistant, containing Pecten texanus, 
Pecten georgetownensis. In many places forms the bed of Sycamore 
Creek 1.5 

Blue marl (pipe clay), gray on weathering, and having a very fine texture 5.2 

40 University of Texas Bulletin 


Top of Gryphea washitaensis conglomerate, in bed of creek 2.0 

Further sections of the Weno formation in Denton, Johnson, and other counties have 
just been given in the discussion of the Pawpaw formation (q. v.). 



The Weno and Pawpaw formations can be traced continuously through 
these two regions and their correlation is obvious. As has been already 
noted, the sandstone facies of the Pawpaw formation has been included by 
Taff in his Bokchito formation. This facies is similar at Gainesville, Den- 
ison and Bokchito, and in itself affords insufficient differences to be con- 
sidered as a different formation on the two sides of the Red River. The 
whole Weno formation is also included in the Bokchito formation of Taff. 
Taff's tabulation of equivalencies 1 makes clear that the Bokchito forma- 
tion is to be considered equivalent to the undefined upper part of the 
Georgetown limestone in the Austin quadrangle, but to what formations 
in North Texas is not clear. However, his Caddo formation is described 
as having at its top a bed of oyster shells "similar to those occurring below 
and at the top of the Kiamichi formation" (ibid, p. 6). This is the Den- 
ton marl and has characteristic Denton fossils, and therefore the base of 
the Bokchito formation is to be considered as the base of the Weno. 2 


The Weno and Pawpaw formations have been traced with certainty to 
the Brazos River south of Blum. The regional and facies differences in 
Central Texas make correlation difficult on account of the smallness of the 
known Del Rio fauna. It is presumed that the Exogyra arietina zone of 
the basal Del Rio clay is continuous with that of the Mainstreet limestone 
north of the Brazos near Blum, and that the Nodosaria texana zone present 
in West Texas at the top of the Del Rio just beneath the Buda limestone 1 
but reduced or absent in Central Texas does not correspond to the promi- 
nent Nodosaria zone found at the top of the Weno and the base of the Paw- 

!Taff : Atoka Folio, p. 6. 

2 Stephenson (U. S. G. S., Prof. Paper 120-H, pi. XVIII) places the Denton clay 
member and the Ostrea carinata bed capping it at the base of Taff's Bokchito forma- 
tion; and also, very curiously, puts the "Gervilliopsis bed" near the base of the 
Denton clay. 

3 B6se: Univ. Texas Bull. 1902, p. 19. 

Weno and Pawpaw Formations 41 

paw formations in North Texas. Turrilites brazoensis, also a fossil of very 
limited vertical range, marks the top of the Georgetown limestone and 
the base of the Del Rio clay in Central Texas from the Brazos southwards. 
The basal Mainstreet then is represented by the uppermost Georgetown in 
Central Texas, and the Pawpaw if present by strata lying high in the 
Georgetown, while the bulk of the lower Del Rio (Exogyra arietina zone) 
is Mainstreet and the upper Del Rio is Grayson. 


West of the southern turning point of the Comanchean outcrops in Bexar 
County, the Georgetown limestone and the Del Rio clay preserve their in- 
dividuality into the Trans-Pecos region. At the type locality of the Del 
Rio clay, it is typically developed as a laminated, greenish-blue clay with 
thin instratified arenaceous clay seams, calcareous flags and shell breccia 
(Exogyra arietina and Noslosaria texana) . In lithology this formation 
"varies from a clay to an arenaceous thin bedded limestone." 1 Here the 
limestone facies is beginning to appear. It increases in amount south- 
wards and in the Mariscal Mountains the bulk of the formation is lime- 
stone. On the other hand, at Cerro de Muleros, Bose's subdivision 6, rep- 
resenting Weno and Pawpaw, is a marl with sand and lime, and his sub- 
division 7, representing the Mainstreet is sandstone. The lithological va- 
riations of the Weno and Pawpaw are summarized on page 27. The 
Georgetown, like the Buda, is over much of West Texas a fine grained 
crystalline semi-lithographic limestone, grading northwards into a marlier 
and sandier near shore phase. The same correlation as in Central Texas 
(page 40) holds for these strata. 

The age of subdivision 6 of Cerro de Muleros is delimited by several of 
its fossils. The following fossils have not been found below this subdi- 
vision, nor below the Denton formation in North Texas : Ostrea quadri- 
plicata Shumard, Ostrea marcoui Bose. Pinna guadalupae Bose is un- 
known below subdivision 6 and below the Weno of North Texas. Enallas- 
ter bravoensis Bose, known from subdivisions 5-6, is not known to occur 
lower than the Denton formation* elsewhere. Helicoctyptus mexicanus 
Bose of subdivision 6 is as yet known only from the Pawpaw of North 
Texas, and the same is true of Placosmilia spp., which are probably iden- 
tical with P. bravoensis and P. mexicana. The zone of extreme abundance 
of Gryphea washitaensis Hill so conspicuous in this subdivision is paral- 
leled in North Texas only by that at the top. of the Denton formation. 

'Roberts and Nash: Univ. Texas Bull. 1803, pp. 14-15. 

42 University of Texas Bulletin 

These facts indicate that subdivision 6 is equivalent to the Weno and 
Pawpaw and to part of the Denton formation. The overlying sand, lack- 
ing Exogyra arietina, contains near its top Hemiaster calvini Clark and 
Exogyra whitneyi Bose. The former fossil is upper Washita, Weno to 
Buda, and the latter is known from the Buda, although from the present 
record it is evident that it ranges as low as the Mainstreet formation. 

It may be of interest to add a list of species described from Cerro de Muleros, which 
have been found in North Texas. The number cited is that of the corresponding divi- 
sion at Cerro de Muleros, and the following formation names refer to the location 
of the fossil in North Texas. 

Epiaster aguilerae Bose, 5; basal Fort Worth. 

Enallaster bravoensis 5, 6, 8; Weno to Grayson. 

Holectypus limitis 5; Weno to Grayson. 

Ostrea marcoui 4, 5, 6; Weno to Grayson. 

Pinna guadalupae 2, 6; basal Weno. 

Pecten subalpinus 2, 3, 5, 6, 8, 9; Goodland to Grayson. 

Pecten irregularis 1, 2; Walnut to Kiamitia. 

Plicatula subgurgitis 2, 5, 6 ; Duck Creek to Pawpaw. 

Helicocryptus mexicanus 6; Pawpaw. 

Turbo chihuahuensis, 'Lei Encantada; Weno. 

Tylostoma chihuahuense 1, 2; Glenrose to Goodland. 

Schloenbachia trinodosa 5, 6; Duck Creek. 


It is unquestionable that the aggregation of Pawpaw pyrite ammonites 
here described parallels Pervinquiere's Vraconian fauna more closely than 
it does his Cenomanian fauna. This might mean that the Pawpaw fauna 
is Vraconian, or that some later (Cenomanian) species are included in his 
Vraconian fauna; or the Pawpaw fauna may be one which has persisted 
with little change from its Vraconian ancestors. Scaphites aequalis-like 
species in Texas are known to range from the Duck Creek marl to at least 
the Pawpaw clay; in Europe they are of Upper and Lower Cenomanian, 
Vraconian, or even Albian age, so that this species decides little ; the Paw- 
paw or the Duck Creek aequalis may be contemporaneous with the Vra- 
conian examples. Flickia decides nothing, since the range of the genus is 
unknown and is extended with each new species discovered. Hamites sim- 
plex ranges from Aptien to Mid-Cenomanian. Attempts have been made 
to correlate the Texas Washita division on the basis of Schloenbachia in- 
flata. This brings us face to face with the question, What is inflata? Is it, 
as sometimes claimed, a Schloenbachia with low, sigmoidal ribs and two 
tubercles, one umbilical and one marginal; or is it a Mortoniceras, with 
square volutions and coarse short ribs having three tubercles, an umbilical 

Weno and Pawpaw Formations 43 

and a pair of twinned ventro-marginal ones, as indicated by Pervinquiere? 
If the latter, there is no Duck Creek species known to me that approaches 
it as closely as do several Upper Washita species. For only above the base 
of the Weno do we begin to find fairly large (6-12 inches) coarse straight 
ribbed square coiled ammonites with an umbilical and a twinned marginal 
tubercle ; this is the commonest and most characteristic Weno calcite spe- 
cies, and it abounds in slightly smaller size in the nacreous ironstone Weno 
fauna (Plate 3, figure 11). In the Pawpaw clay the same type is abun- 
dant as small pyritic casts (M. worthense, Plate 1, figures 6-10, 18-19, 26), 
having extremely short coarse ribs with very prominent twinned marginal 
tubercles and a narrow square volution. Again in the Mainstreet lime 
stone the common calcite species has lower, somewhat sigmoid ribs with 
twinned marginal tubercles and a rectangular section. Are any of these 
inflata? If the Vraconian is to be placed in the Weno, which seems pos- 
sible, the whole Cenomanian will have to lie between the Pawpaw and the 
base of the Eagleford shales, which is generally claimed to be the base of 
the Turonian. Again a Duck Creek species similar to Schloenbachia elob- 
iensis has been noted ; but a comparison of Szajnocha's figures and descrip- 
tion indicate that this species is different from his ; its section is much lower, 
and the shell bears spiral circlets which form regular radial rows contain- 
ing numerous imbricated lips, while in the Texas species (known only as 
internal casts) there are radial rows of only a few rounded tubercles; in 
addition, the stratigraphic data given by Szajnocha are inadequate for cor- 
relation with the Texas strata. 

A comparison of the Duck Creek limonite fauna with the African Vra- 
conian yields only slight results. On the theory that the Pawpaw is Vra- 
conian, the Duck Creek could scarcely be placed earlier than the Albian, 
since the Glenrose is with some certainty assigned to the Aptian. But Al- 
bian species' are not apparent in the Duck Creek limonite fauna, whose am- 
monites are preponderantly small species of Schloenbachia and Hamites, 
with scattering Scaphites sp. aff. aequalis. Desmoceras, etc. Hoplites and 
other abundant Albian genera are so far unknown. The fauna on the other 
hand is predominantly Vraconian. This Vraconian aspect appears to end 
with the Duck Creek limestone oj marl, since with the next limonite fauna, 
that of the Denton marl, there seem to be some species with Cenomanian 
affinities. Comparison of the Texas Washita faunae with those of Western 
Europe, examples of which are before me, shows much less resemblance 
than with the Northern African fauna. Common European species, as 
Douvilleiceras mammilare, Schloenbachia varians, S. mantelli, and Holas- 
ter subglobosus have no representatives in the Texas material so far 
known. On the other hand, the Mainstreet, Grayson and Buda faunae are 

listed among other places in: Tomitch: Contributions a la Connaissance de 1'etage 
Albien dans le Sud-Est de la France. Le Mans, 1918. 

44 University of Texas Bulletin 

of a higher Cenomanian type, containing for example Codiopsis sp. aff. 
doma, Tissotia spp., and Acanthoceras spp. ; and Berry states 1 that the Da- 
kota (Woodbine?) flora is of Turonian age. 

On the whole then the Pawpaw fauna is placed provisionally as Ceno- 
manian with much uncertainty as to its exact position. This question will 
be settled when the rich ammonite faunae of the Lower Washita are crit- 
ically studied. The Texas Comanchean sea was transgressive or at least 
not regressive for a long period so that the relatively stationary shallow- 
water conditions may not have encouraged a rapid evolution of these am- 
monites; whatever the cause, they present notable similarities from the 
earliest to the latest pyrite faunae known in the Texas Comanchean. On 
the theory of persistent and nearly stationary species from Vraconian to 
Cenomanian time some nearly similar species should be much extended ver- 
tically in the Lower Washita sediments; further study of the proper ma- 
rine facies of each stratigraphical level should reveal these and by filling in 
the great gaps in our paleontological knowledge give a fairly complete 
faunal succession. It is hoped that information on the extent of the various 
marine facies in the Texas Comanchean formations will contribute to this 


The rich Weno and Pawpaw faunae initiate a new group of species after 
the considerable paleontological break which occurs at the top of the Den- 
ton marl. The Werio formation, besides containing characteristic ammon- 
ites, is notable in its marl facies for an exuberant echinoid fauna, and in 
its shale facies for a great abundance and variety of distinctive cephalo- 
pods, pelecypods and gastropods preserved with the original nacreous shell. 
Certain elements of this nacreous fauna forcibly remind one of the Eocene 
faunae, with which they have many genera in common. The fossils are 
perfectly preserved, often with iridescent luster, and the original shell 
shows the minutest details : in pelecypods, prodissoconch and other embry- 
onic stages, ligament, and usually the finest features of dentition and ex- 
ternal ornamentation ; in the cephalopods, the original pearly or iridescent 
shell, and beneath this, finely preserved sutures etched into the ironstone 

The Pawpaw formation on the other hand contains a diverse and char- 
acteristic assemblage of small pyritic ammonites, echinoids, pelecypods, 

iBerry: U. S. G. S., Prof. Paper 84, pp. 71, 128. 

Weno and Pawpaw Formations 


gastropods, corals and other fossils. 1 This fauna has close resemblances to 
that described by Pervinquiere- from the Vraconian of Tunis and Algeria, 
a subject that will be considered later. 

The later Washita seas were transgressing over extensive land areas 
and a large numerical expansion in the marine fauna occurred, probably 
in part in the invaded trough already described. In addition, the portion 
of the ocean bottom which received the mixed clay and sand deposits was 
probably at a moderate depth and not far offshore, and permitted a wealth 
and variety of fauna. Note the complexion of life in the Pawpaw seas: 
swarms of sharks and dogfish; a multitude of bottom-loving Crustacea, 
small crabs and lobsters, echinoids, oysters and scallops ; sessile corals and 
worms; pelagic protozoa; a few large, free-swimming nautili and irides- 
cent-shelled ammonites, and a great diversity of small ammonites. 


Of the large and well preserved Weno fauna only a few species have 
been mentioned in the literature, as follows : 
Hill 3 listed the following fauna from the North Denison sands (=Weno) : 

Axinea sp. Tapes sp. 

Nuculaea sp. Turritella sp. 

Corbula sp. 

And the following from the Pawpaw shales and the North Denison 
sands (not separated) : 

Turritella sp. (predominant) 
Corbula sp. 
Axinea sp. 
Volsella sp. 
Tapes sp. 
Cytherea sp. 
Tellina sp. 
Aricula sp. 

Gervilliopsis or Gervillea 
Area sp. 
Nucula sp. 

Ammonites emarginatus Cragin 
Spherwdiscus belviderensis var. 
eerpentinum Cragin 

Trigonia emoryi Conrad 

Pholadomya postextensa Cragin 

Cyprimeria (large sp.) 

Anchura, White 

Lcda 2 spp. 

Mactra sp. 

Dentalium sp. 

Scularia sp. 

Ostrea quadriplicata Shumard 

Pecten inconspicuus Cragin 

Yoldia microdonta Cragin 

Turritella seriatim-granulosa Roemer 

Astarte sp. 

throughout this paper an asterisk (*) preceding the name of a fossil indicates that 
the fossil has pyrite, limonite or hematite preservation; a double dagger (J) indicates 
nacreous preservation. 

2 Pervinquiei - e: fitudes de Paleontologie Tunisienne. Paris, 1907. 

'Hill: Bull. Geol. Soc. Amer., 5, 1894., and 21st Ann. Kept., U. S. G. S. pt. 7, p. 277, 

46 University of Texas Bulletin 

The following species of the fauna have been described by Cragin: 1 
Pecten inconspicuus Tellina subaequalis 

Pholadomya postextensa Sphenodiscus emarg'.natits 

Corbula crassicistata Engonoceras belviderensis var. serpen- 

Tapes denisonensis tinum 

The following species were listed by Stephenson: 2 

Nucula sp. Cymbophora sp. 

Ostrea quadriplicata Shumard Turritella sp. 

Protocardia texana (Conrad) Anchura mudgeana White 

Cyprlmeria sp. Engonoceras serpentinum Cragin 

Corbula 3 spp. Crustacea 

An incomplete list of the Weno fossils on hand is given in the accompany- 
ing table (Table 1) ; many species were omitted for further study. 


The range as given in this table will demonstrate that one of the major 
paleontological breaks in the Washita division lies at the base of the Weno 
formation. The contact between the Denton and Weno formations is ap- 
parently conformable, and many species cross it ; but a considerable num- 
ber of others do not range higher than this contact while another consid- 
erable group does not range lower. Without speculating as to the origins 
of the latter group, it may be delimited more closely in view of a more 
detailed study. 

* Pyrite, limonite or hematite preservation. 
I Nacreous preservation. 
A Abundant 

R Rare 

S Sand phase 

SH Shale phase 

M Marl phase 

L Limestone phase 

u upper part of formation 

m middle 

1 lower 

1 Cragin: Colo. Coll. Stud., 5, 1894, p. 49. 

2 Stephenson: U. S. G. S., Prof. Paper 120-H, 1918, p. 141. 

Weno and Pawpaw Formations 47 

601 Pit of Gainesville Brick Company, brickyards one and three-fourths miles south- 

east of Gainesville, Texas, just east of Rock Creek (branch of Pecan Creek) 
and just south of the Missouri, Kansas and Texas railway (Wichita Falls 
branch). Includes the ironstone dump on east rim of pit. Shale faciee 
basally; ironstone and sand facies above. 

602 East bank of Sycamore Creek, two and one-half miles southeast of Fort Worth, 

Texas. Marl facies basally; limestone facies above. 

604 Cut of St. Louis and San Francisco railway, three-fourths mile north of Union 

Station, Denisoh, Texas. Shale facies basally; ironstone and sand facies 

605 A branch of Duck Creek, three-fourths mile north of Union Station, Denison. 

Texas, and just west of locality 604. Shale facies. 

606 Exposure in valley just south of St. Louis and San Francisco track, two miles 

north of Denison, Texas. Shale facies. 

611 Waterfall 200 yards south of crossing of International and Great Northern rail- 

way over Houston and Texas Central railway track near Sycamore Creek, 
three miles southeast of Fort Worth, Texas. Marl facies. 

612 Cliff on northeast bank of Sycamore Creek, 100 yards north of the Houston and 

Texas Central railway bridge across Sycamore Creek, three miles southeast 
of Fort Worth, Texas. Marl facies basally; limestone facies above. 
618 Area in valley east of Armstrong Iron Works, South Hemphill street, Fort 
Worth, Texas, and west of the International and Great Northern railway 
track. Marl facies basally; limestone facies above. 


As already stated, the bulk of this fauna is limonitic, pyritic or hema- 
titic, but there are in addition some fossils with calcareous preservation. 
The calcareous fossils are echinoids, pelecypods, a few cephalopods and 
other miscellaneous fossils. The echinoids of the basal portion of the for- 
mation are mainly limonitic, but those of the upper, marlier portion over 
all of the Pawpaw outcrops except in the Red River region, are calcareous 
mud-filled tests. 


714 One-fourth mile south of the International and Great Northern railway bridge 
across Sycamore Creek, four and one-half miles southeast of Fort Worth, 
Texas. Entire thickness of Pawpaw, somewhat overwashed at top; north- 
eastward facing slope of hillside, and beneath the slope a considerable terrace 
on the top of the Weno limestone. Clay facies basally; some marl at top. 

716 Amphitheater one-half mile northeast of locality 714. Entire thickness of Paw- 
paw formation exposed. 

716 Pit of Cobb Brickyards, one-fourth mile east of Sycamore Creek and three miles 
southeast of Fort Worth, Texas. 

718 Cut of International and Great Northern railway track one-fourth mile south of 
bridge across Sycamore Creek, four and one-half miles southeast of Fort 


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JTurbo sp. aff. chihuahuensis 
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Turritella worthensis Adkins ... 
JTu-rritella graysonensis 
JAnchura mudgeana White 
ICerithium SD. _ 

















Cinulia sp. aff. pelletti 

Tr.intiiia on 

Amberleya graysonensis 


tGervilliopsis invaginate (Wh 
Pecten subalpinus (Bose) 
texanus Roemer 

georgetownensis Kniker 

Gryphea washitaensis Hill 
Ostrea quadriplicata Shumard 
Ostrea carinata ? Lamarck _. 

Ostrea sp. afT. diluviana Lanu 
Ostrea sp. (small, zigzag) 
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Trisronia clavigera Cragin 
Barbatia simondsi 1 Whitney 


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Weno and Pawpaw Formations 51 

Worth, Texas, and one-eighth mile east of locality 714. Upper part of Paw- 
paw formation, partly marl, overlain by Mainstreet limestone. 

719 Crowley Road, one mile south of the Baptist Seminary, and four! and one-half 

miles south of Fort Worth, Texas. Westward facing cut in hillside, exposing 
poorly most of the Pawpaw formation. 

720 Rim of Weno escarpment one mile southeast of Riovista, Texas, and midway 

between the Riovista- Waco pike and the Santa Fe track. The Pawpaw, simi- 
larly exposed between the Mainstreet and Weno limestones, continues west- 
ward to the next locality. 

721 East-west escarpment just east of Riovista-Waco road, one mile south of Riovista, 

Johnson County, Texas. The Pawpaw is much thinned, and is transitional 
between clay and marl facies. 

722 Cut of Missouri, Kansas and Texas railway (Wichita Falls branch) at north 

end of pit of the Gainesville Brick Company, one and three-fourths mile? 
southeast of Gainesville, Texas. 

723 Westward facing hillside lying under Mainstreet upland on west side of Mans- 

field Road, halfway between Glen Garden Country Club and Sycamore Creek, 
three miles southeast of Fort Worth, Texas. 

724 Hillside on north side of east-west road, three miles southeast of Haslet, Tarrant 

County, Texas. Whole thickness of Pawpaw. 


S : Sand facies ; C : Clay facies : M : Marl facies : L : Limestone facies ; A : Abundant : O : Occasional : 
R: Rare; 1: lower third of Pawpaw iteration ; m: middle portion of Pawpaw formation; u: upper portion 
of Pawpaw formation ; * : Pyrlte or limonite preservation ; } : nacreous preservation. 





718 719 
M C 


724 722 

720 721 
M M 
R R 







FHckia boeaei Adkins ._ 























Turrilites worthensis Adkins and Winton 
Turrilites sp. B. Adkins and Winton 







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an. indet. (vertebrae) _ 









(below Weno formation) 

Holectypus planatus Roemer 
Enallaster texanus Roemer 

Hemiaster whitei Clark and E. elegans 

(Weno and higher formations) 

H. limitis Bose 

E. bravoensis Bose 

E. riovistae Adkins 

E. wenoensis Adkins 

E. sp. aff. texanus Roemer 

H. calvini Clark 

'Weno and Pawpaw Formations 53 

Epiaster aguilerae Bose E. wenoensis Adkins 

Holaster simplex Shumard H. sp. 

Cyphosoma texana Roemer C. volanum Cragin 

Salenia mexicana Schlueter and S. texana 

Credner S " V lana Whlt " ey 

Goniopygus sp. G. budaensis Whitney 

Goniophorus sp. 1 G. sp. 2. 



It has been pointed out' that the North Texas Comanchean system con- 
tains a series of alternate lime and marl (or clay) formations, some of 
which contain conspicuous pyrite and limonite faunae ; these are 

(1) The Kiamitia formation; 

(2) The Duck Creek marl; 

(3) The Denton marl; 

(4) The Pawpaw clay; 

(5) The Grayson formation; 

(6) The Del Rio clay. 

Many pyrite and limonite species are common to these six formations, 
and still others have more restricted vertical ranges and are confined to 
limited levels within a single formation. In general it may be said that 
these fossils are of distinct species from those otherwise preserved in the 
same formation ; that they are rare in the intervening formations, and that 
the complexion of the limonite faunae is different from that of the other 
faunal components of the formations in question. In addition there seem 
to be certain limonite species in the various intervening limestone forma- 
tions, especially in the Fort Worth and Weno limestones. To assist in de- 
termining the age and correlation of these formations the following pro- 
visional fossil lists are given. The list for the Pawpaw formation will 
be found on page 51. 

The rather regular alternation of marl (or clay) and lime formations 
in the North Texas section suggests some form of cyclic deposition, in 
which the same marine conditions were many times repeated, and this 
inference is equally strong for the contained pyrite faunae, when it is 
found that they occur prevailingly in the alternate, clay, formations. This 

'Winton and Adkins: The Geology of Tarrant County, Univ. Texas Bull. 1931. 

54 University of Texas Bulletin 

does not imply that in certain formations no pyrite faunae will be found ; 
they existed somewhere during the whole Washita at least, and likely will 
be found in the clay facies of each formation, just as representatives of 
the Mainstreet pyrite fauna have been found in the clay facies (Del Rio) 
of Central Texas, though apparently absent in the limestone of North Texas. 
It is certain that exuberant pyrite faunae are associated with clay facies ; 
and accordingly the greatest abundance of pyrite fossils in the Kiamitia 
is in southern Tarrant and Johnson counties ; Denton formation, Denison 
to northern Tarrant County; Pawpaw formation, Tarrant County; Main- 
street formation, McLennan County and southward ; middle Grayson form- 
ation, Denton County. In each instance the lithology of the region men- 
tioned is largely of the clay facies. These facts suggest recurrent similar 
conditions which favored the spread of pyrite faunae. At a given locality 
this recurrence might be many times repeated ; and such pyrite zones are 
still being discovered at new stratigraphic levels. What these conditions 
and their causes were will not be discussed here. They resulted in each 
zone in a highly characteristic pyrite and limonite fossil association, which 
is as follows: Area washitaensis, Engonoceras sp., Scaphites spp., Tur- 
rilites spp., Hamites spp., Cinulia sp., Nerinea sp., Lunatia sp., Turritella 
sp-, pyritic starfishes, and abundant small, non-pyritic Crustacea, especially 


The marl facies of the Kiamitia formation extends from Primrose, 
southwest of Fort Worth, to a point between Gainesville and Fink, on 
the Red River. The clay facies extend from near Primrose to at least 
the Brazos River ; it is found throughout Johnson County, and on Cedar 
Creek near Blum is a reddish clay 19 feet thick. With the advent of 
the clay facies the shell conglomerates of the northern section disappear 
and a pyrite fauna similar to that of the Duck Creek marl appears. This 
little investigated fauna contains Area sp., and other small pyritic and 
limonitic pelecypods and gastropods. 


This fauna is notable for its large number 'of small pyritic and limo- 
nitic gastropods and pelecypods. Such genera as Cerithium, Cinulia, 
Turritella, Turbo, Lunatia, Area, Nucula and Corbula are highly char- 
acteristic of the lower Washita pyrite zones. Equally characteristic if 


Weno and Pawpaw Formations {> 

the exceptional variety of gerontic ammonites, especially Hamites; Scaph- 
ites, Schloenbachia, Desmoceras and other genera are also prominent in 
the fauna. 


*Scaphites worthensis Adkins and Winton. 
*Scaphites sp. aff. worthensis. 
*Engonoceras sp. 

Hamites tanima Adkins and Winton. 
Karaites spp. 
*Crioceras (?) sp. 
Schloenbachia sp. 
*Neolobites (?) sp. 

*Arca sp. 
*Nucula sp. 

*Turbo sp. 

*Lunatia sp. 

*Cerithium sp. 

*Nerinea sp. aff. pellucida Cragin 

*Cinulia sp. 

*Anchura sp. 

*Turritella sp. 

*Nerinea sp. 

*Placosmilia sp. 


The clay facies of the Denton formation extends from northern Tar- 
rant County (Blue Mound, near Haslet) to beyond Denison. It is char- 
acterized by a great diversity of small pyrite and limonite ammonites, 
some of them nacreous, and by many small Crustacea, mainly small pyritic 
crabs. The ammonites seem more abundant southwards than on the 
Red River and the Crustacea the reverse. 


* Limonite or pyrite species. 
U Upper. 
L Lower. 

*Acanthoceras sp. aff. aumalense Coquand 
*Engonoceras sp. 
*Mortoniceras sp. 

56 University of Texas Bulletin 

*Schloenbachia sp. 
*Acanthoceras (?) sp. 
"Turrilites sp. (?) 
*Baculites (?) sp. 

Ophioglypha texana Clark 
*Starfish sp. (ray) 
*Goniophorus (?) sp. 2 specimens, one with the shell. 

Leiocidaris sp. (spine and plate). 

Leiocidaris hemigranosus Shumard. 

Hemiaster sp. (plate). 

Hoploparia sp. 

Cambarus (?) sp. (like sp. in Gainesville brickyards Weno). 

Crabs 9 spp. 

Ostrea quadriplicata Roemer. 

Ostrea carinata Lamarck. 

Gryphea washitaensis Hill. 

Ostrea sp. (small zigzag). 

Stearnsia robbinsi White (?). 

Gervilliopsis invaginata White (?) 

Trigonia emoryi Conrad. 

Plicatula dentonensis (?) Cragin. 
*Arca sp. 

Anomia sp. 

Plicatula spp. 
*Nucula sp. 
*Cardium sp. 
*Leda sp. 
*Corbula sp. 

Pecten sp. aff. inconspicuus Cragin. 

Crania sp. 

Dentalium sp. 
?Porocystis-like masses. 

*Natica sp. 
*Cinulia sp. 

Fish teeth, vertebrae, skin, plates. 


The pyrite and limonite fauna so far discovered in the Grayson forma- 
tion is confined to the middle clay member of the formation in North 
Texas, and includes diverse ammonites, gastropods and pelecypods, as 
listed below. However, the pyrite fauna of the middle Del Rio clay 
which occurs in McLennan County and southward is of Grayson age, 

Weno and Pawpaw Formations 57 

and contains some identical species. This latter fauna is well developed 
on the South Bosque River, five miles west of Waco and includes Turrilites 
bosquensis Adkins, Flickia ( ?) bosquensis Adkins, Acanthoceras worth- 
ense Adkins, Schloenbachia spp. and other common Grayson and Pawpaw 
pyrite species. It is notable that the preservation of this fauna is almost 
exclusively pyritic. 


* Pyrite or limonite species. 

(C) Cidarid zone. 

(Co) Coral zone. 

U Upper member. 

M Middle member. 

L Basal member. 


Turrilites sp. (medium size) (M). 
"Turrilites sp. aff. worthensis A and W. 
*Turrilites spp. (M). 
*Turrilites sp. (whiplash) (M). 
*ammonite aff. Flickia (small, keelless) (M). 
*Hamites 3 spp. (M). 

Acanthoceras ? sp. (Denison, WSA). 

Acanthoceras spp. 

Engonoceras spp. (L). 
*Schloenbachia spp. 


Hemiaster calvini Clark, 
starfish sp. 
Goniophorus (?) sp. 
cidarid spines 3 spp. (C). 
Cyphosoma volanum (?) Cragin. 
Enallaster texanus (?) Roemer. 
Enallaster sp. aff. traski (?) Whitney. 
Enallaster sp. aff. bravoensis Bose (?). 


Placosmilia (?) sp. (Co). 


Cerithium sp. 

Turritella marnochi (?) White. 

Turritella sp. 

Cinulia pelletti Whitney. 
*Gyrodes (?). 
"Turbo sp. 
Turritella sp. (sharp spired) M. 

58 University of Texas Bulletin 


Gryphea mucronata Gabb. 

Gryphea sp. aff. corrugata Say. 

Exogyra sp. aff. columbae Sowerby (L). 

Exogyra n. sp. (Denison, M). 

Exogyra sp. aff. texana (U, under Buda limestone, Bosque River, W of Waco). 

Pecten texanus Roemer. 

Pecten subalpinus Bose. 
*Arca sp. 

Ostrea sp. aff. subovata Shumard. 

Lima sp. (elongate). 

Lima sp. (quadrate). 

Lima sp. aff. wacoensis Roemer. 

Ostrea sp. (saucer). 

Anomia sp. 

Plicatula spp. 

Protocardia texana (?) Conrad. 

Pholadomya shattucki Bose. 

Tapes sp. 

Inoceramus sp. M. 

Corbula (?) sp. 

Trigonia sp. 

Cyprimeria sp. (small). 

Cyprimeria sp. aff. crassa Meek. 
*Nucula sp. 

*Crassatella (?) sp. ("Remondia"). 
*Barbatia sp. 

Trigonia sp. (large). 
*Isocardia sp. 

Shark teeth, vertebrae, bones. 


The Del Rio limonite fauna is very widespread in Texas, having been 
found at Waco, South Bosque, Austin, Quihi (Medina County), Del Rio, 
Terlingua, and the Solitario. 

In McLennan County at the base of the Del Rio clay, which corresponds 
to the middle of the Mainstreet limestone, an extensive pyrite and limonite 
fauna occurs, including the following: 

*Exogyra arietina Roemer. 
*Turritella sp. 
*Cerithium sp. 
*Turrilites spp. 
*Schloenbachia sp. 

Weno and Pawpaw Formations 59 

*Nerinea sp. 

Lunatia sp. 
Natica sp. 

Goniophorus sp. 

Pecten subalpinus Bose. 

Turrilites brazoensis Roemer. 

The Del Rio pyrite fauna corresponding to the base of the Grayson 
formation of North Texas has already been noted; it includes: 

* Turrilites bosquensis Adkins. 
*Flickia (?) bosquensis Adkins. 
Acanthoceras worthense Adkins. 
*Schloenbachia sp. 

Exogyra arietina Roemer. 

Gryphea mucronata Gabb. 

Gryphea sp. 

Pecten subalpinus (Bose). 

The first named limonite fauna with an extensive calcite microfauna 
immediately overlies the Georgetown limestone and is of middle Main- 
street age. It is seen at South Bosque, and will probably be discovered 
at many places in Central Texas. 

Liddle states that the Del Rio clay throughout Medina County, contains 
great amounts "of dark brown limonitic fragments and fossils.' Good 
localities are a small Del Rio inlier four miles slightly west of north of 
Quihi on the Bandera road, and the main area of exposure just north of 
the inlier. These localities contain limonitic gastropods, *Turrihtes, *Sca- 
phites, small ammonites, and loose *Nodosaria. 

At Loma de la Cruz and other localities in the Del Rio clay lowland two 
miles south and southeast of Del Rio, the basal clay contains limonitic 
*Schloenbachia sp., *Hamites sp., *Scaphites sp., *Turrilites (two species), 
*sp. aff. Flickia ( ?) bosquensis Adkins ; *Pyrina or Cassidulus sp., cidarid 
sp., *Leda (two species) , *Nucvla sp., *Arca sp. *Plicatula sp. ; *Nerinea 
sp. (abundant), *Cerithium spp. and other fossils. 

Along the base of the Reed Plateau, Terlingua, the basal Del Rio clay 
contains abundant brown limonite fossils, the great majority of which are 
various species of Turrilites. The fauna includes : *Nodosaria texana 
Conrad, *T:irrilites (three species), * Acanthoceras sp., *Schloenbachia sp. ; 
*Nucida sp. 

'Liddle, The Geology and Mineral Resources of Medina County, Univ. Texas Bull, 
(in press). 

60 University of Texas Bulletin 

The Del Rio clay surrounding the Solitario Uplift contains a rich assort- 
ment of brown limonitic fossils, including *Engonoceras sp., *Turrilites 
(two species), *Turritella sp., gastropods, *Nucula sp., *Tapes sp., *Nodo- 
saria texana Conrad, and other fossils. 

It may be mentioned that these limonite faunae in Texas are not confined 
to the Comanchean, since & rich fauna was found in the Terlingua beds 
(Taylor marl equivalent) about five miles north of the crossing of the 
Alpine-Terlingua road through Terlingua Creek, Brewster County, Texas. 
This fauna includes: *Turrilites sp., *Baculites sp., *Ptychoceras sp., 
*Desmoceras sp., *Trochosmilia sp., *Lingula sp., *Lunatia sp., *Natica sp., 
*Nerinea sp., numerous other gastropods, and fish teeth and vertebrae. 

Bose 1 found a rich Vraconian fauna in limestone blocks covering small 
hills just west of Camacho, Zacatecas, between this station and the Trin- 
idad mine, and west of Opal, Zacatecas, iri the core of an anticlinal hill 
consisting of thin-bedded limestone with lenses and concretions of chert. 
These fossils are mainly silicified, but are! cited here on account of their 
striking resemblances to the pyrite fossils described in this paper. The 
fauna includes typical Vraconian genera, as Phylloceras, Lytoceras, Macro- 
scaphites, Hamites, Hamulina, Ptychoceras, Diptychoceras, Anisoceras, 
Turrilites, Baculites, Desmoceras, Acanthoceras, Ancycloceras, Toxoceras, 
Crioceras, Scaphites, Schloenbachia, Brancoceras and Exogyra. 


The Washita marl and clay faunae contain distinctive assemblages of 
ammonites, Crustacea, starfishes, echinoids, gastropods, pelecypods, corals, 
and other fossils. The Crustacea are preserved partly with the original 
integument and partly with limonite replacement. The other fossils are 
in part calcitic, but mainly limonite and hematite pseudomorphs and casts 
of the interior of the -original shell. 

Ammonites: These are very distinctive for each fauna. Species of 
Schloenbachia abound in each marl and clay formation. Acanthoceras is 
found in the Denton, Pawpaw and Grayson faunae, but not in the Duck 
Creek. Hamites are abundant in the Duck Creek marl and present in 
the other formations. Turrilites abounds in the Pawpaw and is not 
known with certainty below it. Flickia, Hamulina, Baculites and Puzosia 
are known only from the Pawpaw clay. 

ose, On some new Cretaceous Faunas from Mexico, Univ. Texas Bull, (in press). 

Weno and Pawpaw Formations 61 




Duck Creek 

Number i 

jf Known J 

Ipecies in: 

Del Rio 




























Puzosia . . 









Crioceras (?) 


Neolobites (?) . 





Number of Known Species in: 

Duck Creek 

Denton Pawpaw 

Grayson Del Rio 

Species marl 

marl clay 

marl clay 








. . 

genus, indeterminate.. 

1 2 







Holaster 1 



Hemiaster 2 

1? 2 







Enallaster 1 



Goniophorus 1 

1 1 

1? 1 






. . 



. . 

cidarid spines 



'Most of these haVe calcitic preservation. 

62 University of Texas Bulletin 

Of these echinoderms the starfishes and brittle stars have so far been 
found only in the upper formations, Denton and above. The echinoids 
also seem more abundant and varied in the Upper Washita; Enallaster 
particularly shows a development of several species in the Weno and 
Pawpaw formations. Stenonia supernus (Cragin) is known only from 
the Grayson marl. Among the small echinoids, Regularia, especially 
Salenidae, predominate. The Salenidae have a wide distribution and 
their various species seem reliable as horizon markers. 


There is a great variety of crabs belonging to many different genera. 
Of the lobsters a small species of Hoploparia is abundant in the Denton 
marl. Segments of appendages abound in these four formations; claws 
are found in the Duck Creek and Pawpaw and rarely in the intervening 
formations. These Crustacea are for the most part calcareous and ex- 
cellently preserved. In addition there are known in the Texas Coman- 
chean, from the Goodland indeterminate limb segments; from the Duck 
Creek limestone Callianassa sp. claws; from the Fort Worth limestone a 
lobster related to Homarus (Dr. Shuler) ; and from the Weno, two lob- 
sters and an indeterminate claw. A crab and a lobster claw have been 
reported from the Buda. 



Duck Creek Denton Pawpaw Grayson 

Species marl marl clay marl 

Cambarus ? . . . 1 

Hoploparia 1 1 

appendages, indet , . . . . . . . 3 

species, indet . . . . 4 

Callianassa . 1 


species indet. 


The Duck Creek limonite fauna is marked by the relative poverty of 
pelecypods and the relative abundance of gastropods. A small species 
of Area, abundant in the Pawpaw also occurs in the other formations. 

Weno and Pawpaw Formations 63 

The Pawpaw and Grayson each has a considerable assemblage of small 
pyritic and limonitic pelecypod casts. 


Duck Creek Denton Pawpaw Grayson 

Species marl marl clay marl 

Area 1 1 1 1 

Nucula 1 1 1 1 

*Leda . . 1 1 

"Corbula .. 1 1 

*Plicatula 1221 

*Barbatia . . . . ". . 1 

*Isocardia (?) .. .. .. 1 

*Remondia (?) .. .. 1 1 

Lima 1 1 2 1 


As may be seen in the following table, a fauna of small gastropods is 
a feature of the pyrite and limonite fossils in these four formations. In 
the Duck Creek marl these small limonite gastropods are the most con- 
spicuous element of the fauna. 


Duck Creek Denton Pawpaw Grayson 

Species marl marl clay marl 

Natica 1 1 1 1 

Cinulia 1 1 1 1 

*Cerithium 1 . . . . 1 

Turritolla 1 .. 1 2 

*Gyrodes 1 .. .. 1 

Turbo 1 .. 1 1 

Lunatia 2 .. 1 

*Nerinea 2 . . 1 

*Anchnra . 1 


Small corals (Trochosmilia, Placosmilia) occur in the Duck Creek and 
Pawpaw formations, and probably in the Denton and Grayson. There is 
a notable abundance of small sharks (Lamna, Oxyrhina, Ptychodus) in 
the Pawpaw, where teeth, vertebrae, plates, skin and bones are found ; 
the same fossils are found less abundantly in the other formations in 

64 University of Texas Bulletin 

question. These sharks also occur in the intervening limestone forma- 
tions but their abundance in the marls and clays testifies to the favorable 
conditions for their existence. 

In view of the importance which these pyrite faunae may have for 
correlation purposes, it is considered useful to refer to certain pyrite 
faunae of approximately the same age known from Europe and Africa. 
Of these the Vraconian fauna investigated by Pervinquiere shows the 
closest similarities to the Pawpaw fauna here described, notably in the 
ammonites. The bearings of these fossils on the correlation of the Paw- 
paw formation have been discussed elsewhere (page 42). It is evident 
that unless conditions for the pyritization of fossils are worldwide at 
a given time, it is useless to attempt to make exact correlations of Texas 
pyrite zones with particular zones abroad. Instead, those pyrite fossils 
which have limited vertical ranges may, like any other such fossil, be 
used to mark within narrow limits the age of the zone in which the fossil 
occurs. A list of similar Texas and foreign pyrite and limonite species 
is added. 


European Limonite and Pyrite Faunae 1 


Sayn 2 has described a series of pyritic ammonites from the Valangian of Provence 
and Dauphine; this fauna consists prevailingly of species of Lytoceras, Phylloceras, 
Garnieria, Neocomites, Thurmannia, Mortoniceras and Leopoldia. 


In the Haute-Marne, near Montierender are two gray sand layers with pyritic 
ammonites, separated by one meter of clayey sand. 

Upper Level: 

Lower Level: 

Hoplites deluci 

denarius Desmoceras beudanti 

splendens Hoplites deluci 

auritus denarius 

Turrilites catenatus quercifolius 

Hamites rotundus Douvilleiceras mamillatum 


Inoceramus concentricus Hamites alternotuberculatw 

Nucula pectinata Belemnopsis minimus 

iHaug: Traite de Geologic, pp. 1232-1298. 

2 G. Sayn, Les ammonites pyriteuses du sud-est de France. Mem. Soc, Geol. France. 
No. 23, 1901. 

Weno and Pawpaw Formations 65 

Inoceramus concentricus 

Plicatula radiola 
Nucula pectinata 
Area fibrosa 
Trigonia fittoni 
Dentalium decussatura 
Solarium moniliferum 
Cerithium trimonile 

In the Rhone basin (les Baronnies and le Diois) the Albian is bathya] and contains 
a level of small pyritic ammonites: 
Phylloceras alpinum 
Tetragonites timotheanus 
Kossmatella chabaudi miihlenbecki 
Desmoceras latidorsatum 


In the Rhone basin, region of Dieulefit, the Vraconian is represented by black marls 
with pyritic fossils: 

Gaudryceras dozei 
Turrilites bergeri 
Belemnopsis ultimus 

Cerithium lallerianum 1 
Avellana muratelli 

African Pyrite Faunae 

In the province of Constantine Blayac 2 collected the following species, preserved as 
ferruginous molds: 

Upper Level: Lower Level: 

Tetragonites timotheanus Phylloceras velledae 

Kossmatella agassiziana Puzosia mayoriana 

Desmoceras parandieri, etc. paronae 

Desmoceras beudanti 

Douvilleiceras mamillatum 

Turrilites gresslyi 

J J. E. Fallot: fitude geologique sur les etages moyens et superieurs du terrain 
cretace dans le Sud-Est de la France. Ann. des Sciences geol., 1, 268 p., 41 fig., 8 pi., 

2 J. Blayac: Le Gault et le Cenomanien du bassin de la Seybouse et des hautes 
plaines limitrophes (Algerie) C. R. Acad. Sci., CXLIII, 252-5, 1906. 

66 University of Texas Bulletin 


In the province of Algiers, near Aumale, Peron 1 found marls with ferruginous fossils: 

Natica Phylloceras velledae 

Solarium Pozosia mayoriana 

Cerithium Desmoceras latidorsatum 

Nucula Desmoceras beudanti 

Leda Uhligella dupiniana 


The Cenomanian is uniformally represented in Northern Tunis by an alternation, 
indefinitely repeated, of marls and limestones. According to Pervinquiere, 2 only the 
lower part of the stage is fossiliferous. Here a Vraconian fauna is found, with the 
following species preserved as ferruginous molds: 

Phylloceras ellipticum? Kossmat Turrilites Bergeri Brongniart 

Velledae Mich. var. Seresitensis Wiesti? Sharpe 

Pervinquiere Morrisi Sharpe 

Tanit Pervinquiere Scheuchzerianus Bosc. 

decipiens Kossmat costatus Lamarck 

Lytoceras Flicki Pervinquiere Puzosianus d'Orbigny 

cf. Marut Stoliczka Kerimensis Pervinquiere 

Timotheaum Mayor Forbesiceras obtectum Sharpe 

cf. Kingianum Kossmat Saynoceras Gazellae Pervinquiere 

Hamites simplex d'Orbigny Scaphites aequalis Sowerby 

virgulatus Brongniart obliquus Sowerby 

armatus Sowerby Thomasi Pervinquiere 

Baculites baculoides Mantell Puzosia Paronae Kilian 

Puzosia Chirchensis Pervinquiere Mortoniceras Nicaisei Coquand 

Mayoriana d'Orbigny proratum Coquand 

Placenticeras Uhligi Choffat Tunesites Salambo Pervinquiere 

Saadense Th. et. P. Acanthoceras Brottianum d'Orbigny 

Flickia simplex Pervinquiere Martimpreyi Coquand 

Brancoceras Zrissense Pervinquiere Aumalense Coquand 
Mortoniceras inflatum Sowerby with its var, Suzannae Pervinquiere 

subinflata, spinosa and orientalis Stoliczkaia dispar d'Orbigny 

Belemites (Hibolites) minimus Lister 

Pervinquiere 3 has described many Cenomanian ammonites from Algeria, some of them 
ferruginous; the fauna contains Phylloceras, Lytoceras, Hamites, Scaphites, Puzosia, 
Acanthoceras, Turrilites, Mortoniceras, and several other common genera, and is sim- 
ilar to that of Tunis. 

1 A. Peron: Essai d'um description geologique d'Algerie pour servir de guide aux 
geologues dans 1'Afrique franchise. Ann. des Sci. Geol., xiv, art. 4, 202 pp., figs. 1883. 

2 Pervinquiere : Et. pal. tun., Cephalopodes, pp. 417-418. 

3 Pervinquiere, Sur quelques ammonites du cretace algerian. Mem. Soc. Geol. France, 
No. 42, 1910. 

Weno and Pawpaw Formations 


Boule, Lemoine and Thevenin 1 cite from Madagascar a series of sandy 
clays of middle and upper Cenomanian age, containing pyritic fossils. 
These clays are characterized by Acanthoceras subvicinale B. L. & T., 
Scaphites aequalis Sowerby, Belemnites fibula Forbes, Ostrea foisseyi 
Lemoine, and contain Acanthoceras prenodosoides B. L. & T., Phylloceras 
forbesianum d'Orbigny, P. diegoi B. L. & T., etc. 




*Scaphites hilli Adkins and*S. 


Flickia boesei Adkins *F. 

*Acanthoceras worthense *A. 


Acanthoceras sp. *A. 

*Hamitestenawa Adkins and *H. 

Hamites sp. 
*Turrilites worthensis 

Adkins and Winton 
*Baculites comanchensis 

*Mortoniceras worthense 

*Puzosia sp. 
*Lytoceras sp. 
*Metopaster hortensae 

Adkins and Winton 
*Comptonia- wintoni Adkin 
Schloenbachia wintoni 


Corbula Wenoensis Adkin.' 
Pinna guadalupae Bose 
Pecten texanus Roemer 
Pecten subalpinus Bose 
Plicatula subgurgitis 

Ostrea carinata ? 


Ostrea marcoui Bose 
Gryphea washitaensis 

Africa (Tunis) 
aequalis Sowerby 

S. aequalis Sowerby 

simplex Pervinquiere 
martimpreyi Coquand A. 

suzannae Pervinquiere 
simplex d'Orbigny H. 

armatus Sowerby 
wiesti Sharpe 

martimpreyi Coquand 

simplex d'Orbigny 
H. armatus Sowerby 

B. baculoides Mantell 

B. baculoides Mantell 



inflatum var. spinpsum 
paronae Kilian 
marut Stoliczka 

M. parkinsoni Forbes 

C. comptoni Forbes 
S. rostrata 

C. bicarinata Noetling 
P. decussata Goldfuss 
P. alpinus d'Orbigny 
P. alpinus d'Orbigny 
P. gurgitis Pictet 

O. carinata Lamarck and 

O. frons 

O. syphax Coquand 
G. vesiculosa Sowerby 

'Boule, Lemoine and Thevenin, Paleontologie de Madagascar, Cephalopodes cretaces 
des Environs de Diego-Suarez, Ann. de Pal., vol. 1, fasc. 4, pp. 2, 4, 1906. 


University of Texas Bulletin 

Helicocryptus mexicanus 


Holectypus limitis Bose 
Enallaster bravoensis Bosc 
Epiaster aguilerae Bose 
Hemiaster calvini Clark 

H. radiatus Sowerby 

H. cenomanensis Gueranger 
E. lepidus de Loriol 
E. triangularis d'Orbigny 
H. latigrunda Peron and 



i860: Nautilus texanus Shumard, Trans. Acad. Sci., St. Louis, 1, 1856-60. 

1889: Nautilus texanus Hill, Geol. Surv. Texas, Bull. 4, p. 21. 

1893: Nautilus texanus Cragin, Geol. Surv. Texas, 4th Ann. Kept., p. 236. 

1895: Nautilus washitanus Cragin, Colo. Coll. Stud., 5, p. 67. 

1902: Nautilus texanus Shattuck, U. S. G. S., Bull. 205, p. 34, pi. XXIII, figs. 1-2, 

pi. XXIV, figs. 1-2. 
1920: Nautilus texanus Adkins and Winton, Univ. Texas Bull. 1945, p. 32, pi. 20, 

figs. 1-2. 
1920: Nautilus texanus Winton and Adkins, Univ. Texas Bull. 1931, pp. 58, 61, 66. 

This is the commonest Cdmanchean Nautilus, and has a known range 
from the basal Duck Creek limestone (at Denison, Texas) to the Buda 
limestone (at Austin, Texas). It has a zone of abundance in the top of 
the Weno limestone, and one in the top of the Fort Worth limestone. 


The upper Pawpaw clay contains considerable numbers of small Nautili 
of a size about one-third that of Nautilus texanus Shumard. These Nau- 
tili are more closely coiled, have a smaller umbilicus, a much thicker and 
lower volution, and apparently are smooth. The species is not described 
here because of the poor preservation of the material at hand. 

1 Types and figured material are deposited in the Bureau of Economic Geology, 
Austin, unless otherwise specified in the text. The types at Austin are in a metal 
locker in the fireproof vault of the University of Texas Library. Most of the photo- 
graphs were made by Mr. F. Christiansen, Austin, but for some I am indebted to 
Professor John Davis, Fort Worth. 

Weno and Pawpaw Formations 6i) 


HAMITES TENAWA Adkins and Winton 

1920: Hamites tenawa Adkins and Winton, Univ. Texas Bull. 1945, p. 43, pi. 6, fig. 4. 
1920: Hamites tenawa Winton and Adkins, Univ. Texas Bull. 1931, p. 21. 
1920: Hamites sp., Winton and Adkins, ibid., p. 69. 

HORIZON: Pawpaw formation, clay fades, base. 

LOCALITY : About three miles southeast of Haslet, Tarrant County, 
Texas (type locality); 714, near Fort Worth, Texas; 723, Glen Garden 
Country Club, near Fort Worth, Texas. 

Among several Hamites in the Pawpaw clay is a straight equal ribbed 
species resembling Hamites simplex. The species and its suture have 
been figured elsewhere; the suture has six lobes and six saddles, mainly 
bifid and slightly dissected. 

HAMITES sp. aff. ARMATUS Sowerby 

HORIZON: Base of the Pawpaw formation, clay facies. 

LOCALITY : 714, near Fort Worth, Texas. 

Fragments of a small Hamites preserved in hematite and showing on 
every second or third rib lour tubercles, two lateral and two ventral, are 
found in the basal third of the Pawpaw clay. The suture is rather similai 
to that of Hamites armatus Sowerby and has the following characteris- 
tics : Suture consists on each side of three saddles and two lobes, in ad- 
dition to the siphonal and antisiphonal lobes ; suture much more dissected 
than that of Hamites tenawa; siphonal saddle narrow and low, with three; 
rounded subdivisions; siphonal lobe narrow, bifid, each lobule narrow at 
base, trifid terminally; first lateral saddle longer and much broader than 
siphonal lobe, flared terminally, bifid, each division twice bifid and laterally 

'In coiled ammonites the external margin of the volution (often keeled) is ventral 
and the internal, concealed margin is dorsal; the sides of the volution are the flanks, 
the terminal opening is the aperture. Lobes point backwards, away from the aperture, 
and saddles forwards, toward the aperture. The siphonal (external, ventral) lobe lies 
on the ventral mid-line and its angulated lobules point backwards; the antisiphonal 
lobe lies on the dorsal mid-line and its lobules point backwards. Next to the siphonal 
lobe and on each side of it is the first lateral saddle, and dorsal to it the first lateral 
lobe ; still more dorsally the second lateral saddle, then the* second lateral lobe. Further 
saddles and lobes are numbered seriatim and are often called adventitive elements. 
In straight shells (Hamites, Baculites, Ptychoceras, straight portions of Scaphites) 
and in fragments of Turrilites, the siphuncle should first be located; the siphonal lobe 
lies upon it. 

70 University of Texas Bulletin 

dissected; first lateral lobe narrow, laterally dissected, twice bifid term- 
inally; second lateral saddle slightly broader, twice bifid; second lateral 
lobe lower, simpler, bifid, dissected laterally; third lateral saddle low, 
broad, rather simple, twice bifid; antisiphonal lobe very simple, rounded, 
slightly trifid at tip, nearly twice as tall as broad. 


PL 11, fig. 1 
1920: Hamites sp. B. Winton and Adkins, Univ. Texas Bull. 1931, p. 22. 

MEASUREMENTS: Diameter of shell without tubercles, dorsoven- 
tral, at small end of fragment 19 mm., at middle of curve, 28 mm., at 
large end of curve 25 mm. ; same diameters, right-left, respectively, 16.5 
mm., 22 mm., 24.5 mm. Number of ribs in 5 cm. along straight portion, 
7; on curve, 4; average number of dorsal costellae per centimeter, 6. 

HORIZON: Base of Weno formation, marl facies. 

LOCALITY : 618 (type locality) , middle exposure, about 10 feet above 
the top of the Denton marl, near Fort Worth, Texas. The type, consist- 
ing of three fragments, and a fragment of another individual were found 

DESCRIPTION : Two limbs connected by a curve ; of these a greater 
part of the thicker limb and a part of the thinner limb are missing. There 
is not enough of the curve present to detect a spiral winding of the 
coil. The smaller, ascending limb increases moderately in diameter to 
the curve, where the fragment has its greatest thickness. There are 
four symmetrically placed rows of prominent, rather slender spines, two 
ventro-lateral and two mid-lateral. The spines of the two ventro-lateral 
rows are coarser and are laterally flattened at the base ; those of the mid- 
lateral rows are more slender and are circular at the base. These spines 
are widely spaced, and a set of the four spines lies on each rib. The ribs 
are coarse, remote, and in a plane nearly at right angles to the long axis, 
however, they slant ventrally towards the aperture, and dorsally from the 
last line of tubercles are continued as obscure elevations which cross the 
dorsum as narrow, fine ribs. The four rows of tubercles bound three 
flat longitudinal strips, one mid- ventral and two ventro-lateral; the re- 
mainder of the circumference is evenly curved. The cross section of the 
shell is therefore hexagonal in its ventral half and short oval in its dorsal 
half. Shell and suture are preserved. 

Weno and Pawpaw Formations 


SUTURE : Similar to that of Ancycloceras lineatus Gabb 1 and Hamitet 
quadrinodosus Jimbo.- Suture consists of medium sized siphonal lobe 
small antisiphonal lobe, and large, nearly equal, first and second lateral 
lobes and first and second lateral saddles ; the third lateral saddle is smaller. 
Details of siphonal lobe indistinct; the next four elements are large, 
slender, spreading, subequal, much dissected, primarily bifid, the subdivi- 

Fig. 2. Ancycloceras bendirei n. sp., suture of the type individual, camera lucida 
drawing, x 5. SL Siphonal lobe; ASL Antisiphonal lobe. 

sions bifid, and the resulting inflections generally minutely trifid, some- 
times bifid, at the tips. These four elements are subquadrate and sub- 
equal. The third lateral saddle is smaller, laterally dissected and twice 
bifid terminally. The antisiphonal lobe is about twice as tall as wide, 
laterally dissected, and trifid terminally, the central prolongation being 
the longest. 

This species is not closely similar to any known to me. It has some- 
what the form of Hamites obstrictus Jimbo, but differs in having four 
rows of prominent slender spines, and in the ribs, which are coarser and 
more widely spaced. Superficially also it resembles in form Ancycloceras 
matheronianum d'Orbigny (Neocomian), but differs from this species in 
the suture, especially in the size of the siphonal lobe and the amount of 
dissection of the lateral elements, in the diminished lateral ribs and in 
the presence of spines throughout the length of the coil instead of tubercles. 


PI. 2, figs. 23-26 

This fossil has two non-contiguous straight limbs united by a single 
curve, and furthermore the suture has six lobes in all, like Hamulina hamus 

'Gabb, Geol. Snrv. Calif., Paleontology, vol. 2. p. 139, pi. xxiii, fig. 18c. 
o, Pal. Abh., vi, 3, 1894. 

72 University of Texas Bulletin 

(Quenstedt) and H. quenstedti Uhlig. 1 The juvenile portion of the shell, 
absent in the material at hand, may have been a close coil as in Macro- 
svaphites, as indicated by the grooved impression on the long limb, but this 
is not certain, and in addition the suture forbids identification with Macro- 
scaphites. The suture and the absence of ribbing prevent its reference to 
Ancycloceras. Bose 2 describes a similar Hamulina sp. from the Vraconian 
limestone blocks of Camacho, Zacatecas. 


I (type) II III IV 

Length of fragment 7.8 mm. 10.0 8.9 8.1 

Width, lower end 1.6 1.0 1.5 1.7 

Width on bend 3.0 2.1 2.2 

HORIZON : Base of the Pawpaw formation, clay facies. 

LOCALITY : 714, near Fort Worth, Texas. The type and two other 
individuals have been found here. 

Three fragments of a straight limbed ammonite, all lacking the aper- 
ture and part of the larger limb, were found in the basal Pawpaw clay. 
In the absence of better material their systematic position can not be set- 
tled, and I assign them with hesitation to the genus Hamulina. The 
curve connecting the larger limb is preserved, but this limb made no im- 
pression on the inner face of the smaller limb, as in some Ptychoceras, 
and therefore was not in close contact with it; in addition, the visible 
portion of the curve is open, indicating a distant, possibly short, thick 
limb. This might suggest Hamulina or Ancycloceras, which mostly differ 
in their sutures and their prominent ribbing. Whether there were three 
limbs as in Diptychoceras, is unknown ; however, the suture is very differ- 
ent from, and less dissected than that figured by Gabb for his Diptycho- 
ceras laevis (laeve) 3 and that species also differs greatly in form from 

Two other individuals (Plate 2, figures 23-25) show distinctly the curve 
and the proximal portion of the shorter, thicker limb. This is free, and 
is separated from the thinner limb by the space of about half of its 
thickness. The aperture is not visible. One individual (Plate 2, figures 
23, 25) shows also a part of the curve at the lower end of the slender 
limb. This end turns with about the same curvature as that of the larger 
curve, and on the venter of the lower end of the slender limb is a wedge- 

iPervinquiere, fit. pal. tun., Ceph., pp. 88-89. 

2 B6se, On some new Cretaceous Faunas from Mexico, Univ. Texas Bull, (in p'ress). 

"Gabb, Pal. Cal., II, pp. 142-5, pi. xxv, fig. 21a-b. 

ana fa^^Kiw Formations 73 

shaped groove about 1 mm. long with the shallowing, pointed end towards 
the aperture, which indicates that the lower end of this ammonite was a 
close coil, as in Ancycloceras, or a closely apposed limb. These three 
individuals agree essentially in their sutures. 

DESCRIPTION: Only fragments preserved, showing a small limb, 
the curve connecting with the larger limb, and a portion of this limb. 
Suture present ; shell, aperture and lower portion of slender limb absent. 
The curve, in the type individual does not quite turn to a position parallel 
to the small limb; and the two limbs are not in contact, at least at the 
curve. Dorsal side with a central and two lateral flattened smooth strips 
(the antisiphonal lobe lies on the former), making the cross-section near 
the turn a very thick crescentic or kidney bean shape, slightly concave 
dorsally and broadly convex ventrally. The smaller limb is slender in 
its younger stages and thicker to a point near the curve; here there is a 
slight dorsal inflation beyond which are no sutures; farther up, at the 
curve, there is a slight dorsal constriction. The ventral mid-line bears 
a small ridge which apparently marks the siphuncle. 

SUTURE : The suture is but slightly dissected, and consists of two 

Fig. 3. Hamulina worthensis n. sp., Sutures of type individual, camera lucida drawing, 
x 16. 

lateral lobes and three saddles, in addition to the siphonal and 1 anti- 
siphonal lobes. The siphonal lobe is bifid and has two slender elongate 
tips ; it is about twice as tall as broad. The first and second lateral saddles 
are nearly equal and similar; each is about half as tall as broad, and is 
bifid by a shallow, simple lobule. The first lateral lobe is trifid and pro- 
gressively diminishes in size from the younger to the older sutures. The 
second lateral lobe is rather smaller than the first, and is bifid. The third 
lateral saddle is of the same height and about half the width of the other 
two, and is broadly rounded and unequally bifurcated by an angular notch 

74 University of Texas Bulletin 

lying nearer the antisiphonal lobe and making the more dorsal division 
smaller than the more lateral one. The antisiphonal lobe is peculiarly 
narrow and elongated, and has a slightly inflated, bifid tip. 

The suture has the same number of elements, six lobes and six saddles, 
as Ptychoceras, and the species seems to have some resemblance to 
P. laeve, var. hamaimensis Pervinquiere 1 (Lower Gault, Tunis) ; however, 
the first two saddles of our species are broader and less dissected; the 
third saddle is unequally and shallowly bifid ; the first lateral lobe is 
trifid instead of bifid ; and the other lobes are bifid. The African species 
also differs greatly in form from ours, in having two apposed limbs and 
annular constriction and inflations on the thicker limb. The Texas Upper 
Cretaceous (Navarro) species Ptychoceras texanum (Shumard) 2 has the 
two limbs strongly ribbed and closely apposed. 


PI. 2, figs. 20-22 
1920: Baculites sp., Winton and Adkins, Univ. Texas Bull. 1931, pp. 21, 69. 


I (type) II III 

Length 12.5 17.3 13.4 

Smaller end, major diameter 3.3 4.0 3.9 

Smaller end, minor diameter 2.9 3.4 3.0 

Number of ribs in 5 mm 5 1-2 

Larger end, major diameter 6.1 

Larger end, minor diameter 3.4 3.7 3.1 

Number of ribs in 5 mm 4 1-2 3 

A characteristic Pawpaw baculite lacking the aperture and the coiled 
portion, will be described here on account of its stratigraphic importance. 
The straight portion is preserved with the sutures, as a limonite cast. 

HORIZON : Pawpaw formation, clay facies, base, rare. 

LOCALITIES: Individual II from locality 714, near Fort Worth, 
Texas; type individual (PL 2, fig. 21) and the others from locality 719, 
wes t facing hill to east of Crowley road, one! mile south of the Baptist 
Seminary, four and a half miles south of Fort Worth, Texas. 

DESCRIPTION: Straight fragments preserved, slightly and uni- 
formally tapering, lateral outlines slightly undulating but on the whole 
straight; cross-section a short oval; living chamber not preserved, but 

'Et. pal. tun., p. 90, pi. IV, figs. 5, 6a-b. 

c. Bost. Soc. Nat. Hist., 8, 1861 (1862), p. 190. 

Weno and Pawpaw Formations 75 

sutures suddenly more crowded at larger end. Ribs consist of evenly 
rounded, low, annular swellings in a plane nearly perpendicular to the 
long axis of the shell, more crowded near the enlarged end, almost equally 
steep on both sides of the annulation, tallest on the venter and on the 
ventral half of the sides, thence decreasing in height toward the dorsum, 
where they turn sharply toward the more constricted end of the shell 
and become obsolete upon crossing the dorsum. Over the more constricted 
lower end of the shell a suture lies in the lower half of the valley between 
each two annulations, but in the thicker part of the shell the relation of 
sutures to annulations is variable; near the thicker end in the type, the 
sutures are crowded. 

SUTURE: Besides the siphonal and antisiphonal lobes, the sutural 
elements consist of three lateral saddles and two lateral lobes. The 

Fig. 4. Baculites comanchensis n. sp., sutures of type individual, camera lucida draw- 
ing, x 8. 

siphonal lobe is bifid, having two slender, rather acute points and a rela- 
tively broad, low, crenulate, external saddle; this lobe is nearly twice as 
tall as broad. The antisiphonal lobe is extremely small and simple; it 
consists of a single long, narrow, rounded point. The first lateral saddle 
is about twice as wide as the siphonal lobe and is deeply bifid by a rather 
simple lobule with one central and two incipient lateral points; each of 
these portions is again bifid. The first lateral lobe is very tall and bi- 
furcated terminally. 1 The second saddle is bifid and not quite as wide 
as the first; of its divisions the ventral one is trifid and the dorsal one 
bifid. The second lobe is broader at the base than the first, and about 
two-thirds the height; it is bifid terminally. The third saddle is broadly 
rounded and shallowly bifid. The suture (Fig. 5) is peculiarly simplified 
and is very characteristic. It is somewhat similar to that of Baculitef, 
vertebralis Lamarck (Santonian), but differs in having a very simple and 
reduced antisiphonal lobe and third lateral saddle, and in the greater 
breadth and simplicity of its first and second saddles. It has even less 
resemblance to Baculites baculoides Mantell (Vraconian), whose saddle? 

'If the lobes are trifid the fossil belongs to Bochianites Lory; however, the suture 
agrees better with Baculites. 

7li University of Texas Bulletin 

and lobes are narrow, much dissected and constricted basally. I have not 
had opportunity to compare this species with other Vraconian and Albiar, 

PL 3, figs. 3, 7 


Height of spire 21 mm. 

Diameter of last volution . 12 mm. 

Aperture, height 7.2 mm. 

Aperture, breadth 6.1 mm. 

HORIZON: Middle of Del Rio clay at top of abundant horizon of 
Exogyra arietina Roemer, in association with Flickia 1 bosquensis Adkins, 
Acanthoceras worthense Adkins, Pecten subalpinus (Bose), Gryphea 
mucronata Gabb, and small pyrite fossils. The turrilite apparently is 

LOCALITY : West bank of the South Bosque River, 150 yards south 
of the bridge on the Speegleville road, tall Del Rio cliff, 5.5 miles west of 
the courthouse at Waco, Texas (type locality) . 

DESCRIPTION: Shell conical, sharp spired, spiral angle 37 degrees 
near tip but spreading slightly on the last volution, sinistral, turreted, 
five volutions in the type, decreasing rapidly in size towards the apex. 
In side view the volutions are more angulated and the tubercles relatively 
more prominent than in any other known Texas turrilite. There are 
four spiral rows of tubercles, of which three are large and nearly equal 
and lie on the prominent flank of the volution and the fourth is diminu- 
tive and lies beneath the upper margin of the volution. The third row 
of tubercles lies at the exact margin between the volutions and is there- 
fore covered as is the fourth small row, by the succeeding volution, so that 
on the earlier volutions only two rows of tubercles are exposed. Of these 
the lower row, nearest the siphuncle, is separated from the lower ex- 
posed margin of the volution by a broad smooth evenly curved spiral 

Tubercles of the first and second rows 1 are obliquely placed and are 
not connected by visible ridges. The third row is closely spaced, the 
tubercles being more numerous than in the first two rows, and this row 

1 Counting from below when the turrilite is placed point down (See Pervinquiere, 
Et. pal. tun., Ceph., p. 428). The siphuncle is then inferior and may be concealed 
by overlap of the next volution. 

Weno and Pawpaw Formations 77 

is separated from the second row by a sharply excavated spiral groove 
of only half the width of the space separating the first two rows. Finally, 
the small tubercles of the fourth row are paired with the tubercles of 
the third row, the tubercles of a pair being connected by an obsolete radial 

The angularity of the volutions is caused by the lateral projection of 
the first and second rows of tubercles. In the type individual, the sec- 
tion of the last volution (pi. 3, fig. 7) is elliptical in its basal (dorsal) 
half, and the inner margin is evenly rounded. The superolateral margin 
is incised between the three prominent tubercles, and the superior margin 
in the region of the fourth line of small tubercles is almost straight. 

SUTURE: The type individual shows a series of suture stages be- 
ginning on the earliest preserved volution. This volution is rounded and 

I .* o/ Q 

1 o2 , * 

Fig. 5. Turrilites bosquensis n. sp., sutures of type individual, camera lucida draw- 
ing, x 8. The numbers indicate the volutions on which the corresponding 
sutures occur. 

is totally smooth and tubercles begin to appear only at a diameter of 
spiral of 2.8 mm. At this point the volution is 1.1 mm. thick and the 
first and second rows of tubercles appear simultaneously. The suture 
is simple and consists of a low, undissected siphonal lobe, a simple first 
lateral saddle, a slightly smaHer and still undissected first lateral lobe, 
a slightly bifid but otherwise simple second saddle, and an undivided 

78 University of Texas Bulletin 

second lateral lobe, of which half is concealed by the next volution. The 
siphonal lobe of the second volution is dissected, and the two lateral sad- 
dles are bifid with simple rounded subdivisions, but the lateral lobes are 
rounded and undivided. On the third volution the saddles become still 
more complicated, in general being trifid, but the lateral lobes have little 
inflection. The siphonal lobe has elongated to its final form but still 
lacks secondary inflections. In the fourth volution the siphonal lobe is 
subdivided laterally, and has mature inflections and form. The lateral 
lobes are slender and trifid, and the lateral saddles are dissected, in general 
twice trifid. The final volution of the type individual has all elements 
of the suture dissected (the siphonal lobe was poorly preserved and likely 
is more dissected than is shown in the drawing) . The first saddle is twice 
as broad as the first lobe and is broadly bifid. The second saddle is bifid 
and the second lobe in this individual indeterminate. 
Number of individuals: about 10. 

PI. 3, figs. 1, 6 

This common Pawpaw species marks the clay phase in the region from 
Denton to Johnson County, Texas. It is more abundant in the basal five 
feet of the formation. The species is rare in the marl transition phase, 
one individual having been found near Riovista. The species is very 
rare or missing in the Red River region. 


PI. 3, figs. 2, 4 

There are several dextral and sinistral turrilites, preserved in hematite 
or pyrite, which characterize the Pawpaw clay, and material is being 
collected for a further study of their structure. In numbers these tur- 
rilites are abundant and are one of the most striking features of the 
fauna. They likewise are rare except in the clay facies, and have not 
been found so far, north of Denton County or south of Johnson County, 
Texas. Turrilites similar to these species have been found in the Del 
Rio clay just above the Exogyra arietina horizon (equivalent of Grayson 
formation) near Waco and Austin, Texas. 

Weno and Pawpaw Formations 79 

SCAPHITES HILLI Adkins and Winton 
PI. 2, figs. 1-12 

1920: Scaphites hilli Adkins and Winton, Univ Texas Bull. 1945, p. 37, pi. 7, figs. 3-6. 
1920: Scaphites hilli Winton and Adkins, Univ. Texas Bull. 1931, p. 21. 
1920: Scaphites sp. A. Winton and Adkins, ibid., pp. 21, 69. 


PI. 2, PI. 2, PI. 2, PI. 2, PI. 2, PI. 2, 

Fig. 1 Fig. 4 Fig. 7 Fig. 8 Fig. 12 Fig. 17 

Greatest length 9.6 9.5 13.5 11.0 8.0 7.5 

Greatest thickness 8.2 4.4 7.3 4.8 7.0 6.5 

Diameter of coil 7.8 3.8 6.0 6.5 7.0 6.2 

Length of uncoiled portion .... 5.0 8.0 7.5 .... ...: 

Thickness of last turn 8.2 4.4 4.5 2.6 2.6 3.6 

Thickness of next to last turn 3.6 3.1 1.5- 

Greatest length of umbilicus 1.8 1.2 2.1 2.0 1.6 1.2 

Number of (ventral) ribs per 

centimeter, on coil 20 28 20 26 32 26 

On uncoiled portion 24 26 .30 

HORIZON: Basal half of Pawpaw formation, clay phase. This 
species has so far not been found outside of Tarrant County, Texas, but 
it may be expected throughout the extent of the clay phase of the Pawpaw, 
or farther. 

LOCALITY: Most frequent at the type locality one-fourth mile south 
of the International and Great Northern Railway bridge across Sycamore 
Creek, Fort Worth, Texas (locality 714), and one-half mile west of the 
Glen Garden Country Club, Fort Worth, Texas (locality 723). 

NUMBER OF INDIVIDUALS : About 25 individuals have been found. 
These are in the Bureau of Economic Geology, Austin, Texas, and Texas 
Christian University, Fort Worth, Texas. 

TYPE INDIVIDUAL: From locality 714 (described above) : deposited 
in Walker Museum, Chicago. 

MODE OF PRESERVATION: Type, dark reddish brown hematite; 
other individuals light reddish yellow limonite; a few scattered pyrite 
cubes noted. 

DESCRIPTION: This scaphite consists of a coiled portion and an 
elongate unrolled portion terminating in the aperture, and at their junc- 
tion there is a prominent dorso-lateral tubercle or geniculation which may 
be taken as an orienting point in describing the ribs and sutures of this 

80 University of Texas Bulletin 

The coiled portion consists of an unknown number (3 or 4 ?) volutions, 
and the umbilicus is deep and, due to the position of the dorso-lateral 
tubercle, has a kidney-bean shape with the end nearer the aperture some- 
what pointed. There is a distinct elongation, which in the absence of 
the uncoiled portion will orient the shell. 

For the most part there are no sutures nearer the aperture than the 
dorso-lateral tubercle, and the uncoiled portion represents the living 
chamber, and therefore lacks sutures. 

Coiled portion ventricose to subglobular, very obese, subovate in out- 
line, evenly and almost circularly rounded ventrally ; dorsally the circular 
margin is broken by the incurved margin of the dorso-lateral tubercle, 
resulting in a more or less open crescentic or tear-shaped umbilicus, lying 
slightly oblique to the axis of the uncoiled portion; greatest transverse 
diameter of coil ventral to this tubercle; coil slightly constricted just above 
the tubercle. The uncoiled portion of which the part below the tubercle 
is the living chamber, is elongate and ornamented with numerous fine 
ribs which course obliquely from the dorso-lateral margins to the venter, 
being nearer the aperture at the latter point. The living chamber is in- 
flated at the edges at the dorso-lateral tubercle where it is in contact, 
with the coil, constricted dorsally at a point a little nearer the aperture 
and thereafter on approaching the aperture is constricted and curved 
dorsally. Its dorsal side is excavated into a prominent groove, whose 
width is about half that of the living chamber, and into which the coil 
fits at the upper end; the groove thus is exposed from the coil to the 
aperture. The resulting cross section of the living chamber is concave- 
convex, the short dorsal concave margin passing over the sharply rounded 
edges of the dorsal groove into the longer lateral and ventral margin. 
This section varies at different points of the scaphite; near the aperture 
it is more concave dorsally. 

FORM : There is a variation in form, amount of embracing and rate 
of increase in size of the successive volutions, as is seen also in the inter- 
grades between Scaphites obliquus and Scaphites aequalis. 1 

The type of Scaphites hilli is an obese individual with thick, rapidly 
expanding volutions, which closely approaches the typical S. aequalis 
Sowerby as figured by Pervinquiere. This expansion over the last volu- 
tion of the coil amounts to a doubling of the breadth of the coil, the 
breadths at the dorso-lateral tubercle and at the point opposite it on the 
next volution being in the ratio of 8:3.6 in the type. The amount of 
thickening interiorly is also great, since the umbilicus is deep. The re- 

'Pervinquiere, Et Pal. Tun., pp. 118-120. 

Weno and Pawpaw Formations 81 

suiting cross-section of the last turn is thickly crescentic (pi. 2, fig. 1). 

The remaining individuals have thick coils but show a less rapid ex- 
pansion of the last volution. One individual (pi. 2, fig. 7) has preserved 
most of the uncoiled portion which is a thick crescent with rounded sides 
and a relatively narrow non-ornamented dorsal groove; the aperture is 
destroyed. Usually only the coiled portion is preserved, and these in- 
dividuals are of variable size, even when the dorso-lateral tubercle is also 
present. They have the same relative thickness and expansion of the coil 
as the individuals of S. aequalis figured by Pervinquiere. 1 It is notable 
that the ribbing becomes obsolete over the lower half of the dorso-lateral 
tubercle and the entire apertural region. 

A straight groove of variable prominence along the ventral midline is 
a feature of all material found. 

RIBS : The ribs are branched or unbranched. They are most numer- 
ous at the ventral mid-line and thence laterally some stop short of the 
dorso-lateral margin and some pass over this margin with a pronounced 
sigmoidal flexure and describe across the dorsum an arcuate curve, con- 
vexed towards the aperture. These principal ribs are thick and elevated 
laterally. In addition there are shorter ribs which are best developed 
at the venter and disappear at both ends, or else branch from a principal 
rib laterally, and crossing the venter disappear laterally, on the opposite 
side of the coil. There is some irregularity in the distribution of these 
types of ribs, as follows: In one invividual (pi. 2, fig. 7) in the region 
at the end of the uncoiled portion there are long and short simple ribs 
and branched ribs but the long simple ribs predominate. In the branched 
ribs the point of branching is far ventral, lying one-third the distance from 
the ventral midline to the dorsal midline. Near the dorso-lateral tubercle 
there are long and short simple ribs with rare incipient branching; the 
short ribs decrease in length, as their ends lie farther from the umbilicus. 
The same statements hold for the other individuals figured. In the distal 
half of the outer volution of the coiled portion a short simple rib alter- 
nates with a -long simple rib ; however, there is incipient branching in the 
long ribs opposite the dorso-lateral tubercle (pi. 2, fig. 7) sporadically 
near the tubercle (pi. 2, fig. 4) or even over the whole distal half of the 
volution (pi. 2, fig. 12). In one individual (pi. 2, fig. 8) there are alter- 
nate long and short simple ribs next to the tubercle, but more proximally, 
there is an irregular alternation of simple and branched ribs. In general, 
this region shows an alternation of long simple ribs with short simple, 
ones, and incipient or developed branching. This is the situation in the 

'Et. Pal. Tun., plate IV, figures 24-26. 


University of Texas Bulletin 

type individual (pi. 2, fig. 1) in which the ribs are at some places evi- 
dently branching, and at other places apparently of alternate length. 

The remaining visible portion of the coil shows in general an alter- 
nation of one branched with one unbranched rib. This alternation is 
often irregular ; in pi. 2, fig. 8 the simple ribs preponderate. The branch- 
Jng may be incipient giving the impression of an alternation of one 
branched rib with two simple ribs or of one long simple rib alternating 
with two short simple ribs (pi. 2, fig. 12) . In one individual (pi. 2, fig. 12) 
a branch from a principal rib at one umbilical margin crosses the venter 
and fuses with the next principal rib, giving a zig-zag ribbing. 

Briefly the ribbing is more branched on the coil and simpler' on the 
straight portion. It is seen that the ornamentation of the coil somewhat 
resembles that of S. meslei Grossouvre (Coniacian), which, however, has 
the principal ribs more prominent and the secondary ribs largely un- 
branched; this species also unrolls much less rapidly than the type of 
S. hilli. The obesity of the typical S. hilli also removes it from S. obliquus 
as does the coarseness of its ribbing; in fact, no individual known ap- 
proaches S. obliquiis in either respect. In both respects it is similar to 
the thick coiled examples of S. aequulis Sowerby, from which it differs 
in the rate of increase of its turns, in the dorso-lateral tubercle and shape 
of the umbilicus, and in the suture. S. aequalis shows the same prom- 
inence of the primary ribs near the umbilical margin and the same branch- 
ing laterally on the coil, as S. hilli. 

Fig. 6. Scaphites hilli Adkins and Winton, suture, type individual, camera lucida 
drawing, x 12. The fossil is figured on PI. 2, fig. 1. 

SUTURE: Figure 6 shows the suture of the type, so far as can be 
seen without dismembering the scaphite. This well developed suture has 
externally besides the siphonal lobe, two conspicuous lobes and near the 
umbilical wall a third irregular, low, wide lobe. Of these, the first lateral 

Weno and Pawpaw Formations 83 

lobe is narrow, very tall, and trifid, with the central point strongly de- 
veloped. The second lateral lobe is broad, nearly the same height as the 
siphonal lobe, its breadth being about six tenths that of the first saddle, 
and is bifid with each lobule split into rounded tips. The third lobe is 
twice as broad as tall and is obscurely split into four rounded divisions. 
The first saddle is large, subquadrate in outline and deeply bifid; each 
division is split by a lobule into two unequal bifid components. The second 
saddle is bifid. The third saddle, which lies on the umbilical wall, is 
wide and low. 

Fig. 7. Scaphites hilli Adkins and Winton, young individual, showing the last five 
sutures, camera lucida drawing, x 10. The fossil is figured on PL 2, figs. 3-4. 

A comparison of the mature suture of the type with juvenile suture 
stages is represented in figure 7. This individual differs from the type 
in many ways ; it is less obese and its coils increase less rapidly ; its rib- 
bing is possibly coarser; its first lateral saddle is shallow and very wide 
and is split by a shallow lobule, whereas it is tall, narrow and split by a 
deep lobule in the type of S. hilli; the two have the same horizon and 
range and are apparently connected by intergrades. The situation is 
somewhat similar to that of Scaphites aequalis and S. obliquus, and until 
further material is available, I would refer this form to S. hitti. This 
suture is seen to be simpler and to lack the finer divisions of saddles and 
lobes seen in figure 6. The lobes on both individuals are, however, bifid. 

84 University of Texas Bulletin 

The internal suture of a small individual whose form and ribbing mainly 
agree with the last named individual is shown in figure 8. This suture 
has six lateral and internal saddles and five lobes. The anti-siphonal lobe 
is trifid, the remaining ones bifid. 


Fig. 8. Scaphites hilli Adkins and Winton, external and internal suture, camera 
lucida drawing, x 10. 

Very closely related to this species is Scaphites worthensis Adkins and 
Winton (Duck Creek marl) which, however, lacks the ventro-lateral tu- 
bercle; its suture also differs in several respects. Scaphites semicostatus 
Roemer and S. texanus Roemer, have been described from the Eagleford 
formation near New Braunfels; S. vermiculus Shumard from the Eagle- 
ford near Woodlake, Grayson County; and S. vermicosus Shumard from 
the Navarro near Dresden, Navarro County. 

PI. 4, figs. 3, 5-6, 12 

1900: Sphenodiscus belviderensis, var. serpentinus Cragin, Colo. Coll. Stud., viii, p. 31, 

pi. 2, figs. 4-6. 
1903: Engonoceras serpentinum Hyatt, U. S. G. S., Mon. XLIV, p. 162, pi. XIX, 

figs. 7-14; pi. XX, figs. 1-5. 
1918: Engonoceras serpentinum Stephenson, U. S. G. S., Prof. Paper 120-H, p. 143. 

This distinctive Engonoceras is frequent in the shales of the Middle 
Weno formation in Grayson and Cooke counties, Texas. Shell nacreous 
in the material studied, with fine, close, sigmoid, radial striae; suture 
simple, as figured by Hyatt (U. S. G. S., Mon. XLIV, pi. XIX, fig. 7) ; 
venter rather square, angulated and rounded at edges, zigzag due to 
alternating marginal tubercles on the two flanks. 

HORIZON: Lower and Middle Weno shale and ironstone; Pawpaw 

LOCALITIES : Frisco cut, three-fourths mile north of Union Station, 
Denison, Texas, and the cut of Duck Creek just west of this locality; pit 
of brickyard, one and three-fourths miles southeast of Gainesville, Texas ; 
Pawpaw bluff on the Red River, northwest of Cedar Mills, Texas. 

Weno and Pawpaw Formations 85 

PI. 4, figs. 8-10 

The most numerous fossil in the basal Pawpaw clay is Engonoceras; 
this genus is rare in the Duck Creek, Denton, Grayson, and Del Rio pyrite 
faunae, and its abundance is diagnostic for the Pawpaw clay as so far 
examined. There is probably more than one species in this formation. 
The individuals are small (one inch or less), hematitic or pyritic, with 
sharply etched sutures; flanks smooth and nearly flat; venter straight- 
edged, angulated, concaved on the midline (so far as observed never acute 
as in Metengonoceras) ; umbilicus narrow; sutures of varying complexity, 
mainly very simple, with numerous auxiliary elements. 

HORIZON: Pawpaw formation, clay facies, abundant: Tarrant 
County, numerous localities; Denton County, Johnson County. 

Grayson formation : marl facies and middle clay member, rare, Tarrant 
and Denton counties. 

Denton clay : rare, Denison to Blue Mound, north of Fort Worth. 

Duck Creek marl: rare, Grayson to Tarrant counties. 


PI. 1, figs. 1-3 
1920: Flickia sp. Winton and Adkins, Univ. Texas Bull. 1931, p. 69. 

HORIZON : Pawpaw formation, clay facies, base. 

LOCALITY : Type individual, base of Pawpaw formation, just or 
top of Weno limestone escarpment, one-fourth mile east of Riovista-Waco 
road and one mile south of Riovista, Texas. One eroded individual, the 
type, was found here. 

MEASUREMENTS : Height of last whorl, 3.5 mm., width, 4.6 mm. ; 
greatest diameter, 10.5 mm ; width of umbilicus, 3.7 mm. 

DESCRIPTION: Form discoidal, inflated, volutions thick, with thick, 
crescentic section, moderately embracing, umbilicus deep, open, showing 
at least five volutions. Cast smooth and unornamented. 

From the section of the end of the coil it is evident that the volution 
at this age embraces only about half of the preceding one; the volutions 
are also much broader and lower than in the adult Flickia simplex, having 
at the end of the fifth (?) volution a ratio of breadth to height of 3:2. 
The flank is broadly convex and passes into the umbilical wall by a sharp 

86 University of Texas Bulletin 

convexity of more than a right angle. The curvature of the venter is 
nearly elliptical ; a keel is lacking, but at the ventral midline of the latest 
part of the coil there is a perceptible rounded angulation. The dorsal 
region of the last volution has a more nearly circular curvature than the 
venter, and the venter of the next younger volution is therefore taller 
and more nearly circular than the outer volution. 

SUTURE : Goniatitic, as in Flickia simplex Pervinquiere, from which 
it differs only in minor details. All of the sutural elements are less tall 
and relatively less slender than in the African species. As in that species 
there are three lateral saddles and three lateral lobes; of these the first 
and second lateral saddles and most of the second lateral lobe lie upon the 
flank, while the remainder of the visible suture lies On the steep umbilical 
wall. The siphonal lobe is bifid with two low, rounded points and a cen- 
tral (external) saddle; the saddle has a greater breadth and is considerably 
less pointed than the lobules, in fact it has a very broad, even, arcuate 
curvature. The first lateral saddle is broad, non-angulate, evenly curved 
and almost as tall as broad; its breadth occupies nearly half that of the 
flank. The first lateral lobe and the second lateral saddle have almost 
the same size and shape: each is rounded terminally, having almost a 
circular curvature, and slightly more constricted basally; and the second 
lateral saddle has in one instance a very slight suggestion of angularity, 
like Neolobites. The second lateral lobe and the third lateral saddle are 
low, broad and non-angular. The foregoing description is from the type 

Fig. 9. Flickia boesei n. sp., type individual, sutures, camera lucida drawing, x 8. 

Pervinquiere 1 established the genus and species Flickia simplex to in- 
clude a small ammonite with simplified suture remotely like Neolobites, 
from the Vraconnian of Tunis. Comparing the latest sutures of the 
two types, 2 ' we find that the first lateral saddle of the Texas species is 
somewhat lower and broader than that of Flickia simplex; the second 
one is higher and lies entirely upon the flank, while in the African species 
it appears to lie partly upon the umbilical wall; the external saddle of 

Pervinquiere: Et. pal. tun., p. 212, pi. 9, figs. 2-5, text figs. 80, 82. 

Weno and Pawpaw Formations 87 

Flickia boesei is lower and more flattened than that of F. simplex; and 
the siphonal lobe is narrower and taller and instead of being inflated, 1 
tapers slightly to the end. The Texas type is probably juvenile, since 
the living chamber is lacking, and since it is more similar to the younger 
than to the older sutures of Flickia simplex. 

Such simplified ammonites afford few visible characters for comparison, 
and therefore separations must be*made on the basis of slight superficial 
differences. Very likely better preserved material will afford a more 
secure basis for distinguishing the species and for defining its relation- 
ships. Provisionally it is placed in Flickia on account of its form ana 
suture. Since the species differs only slightly in form, cross-section and 
suture from Flickia simplex, essentially the same arguments as to its gen- 
eric position hold. It is notable, however, that in the Texas species the 
resemblance to Neolobites suggested by Pefvinquiere is even more striking 
than in Flickia simplex, especially in the very slight angularity of the 

PI. 1, fig. 4; PI. 4, fig. 11 

There has recently come to light a peculiar Flickia-like ammonite, which 
although not belonging to this genus as described by Pervinquiere seems 
to stand closer to it than to any other genus, and is here described on 
account of the possible light that it may throw on the relations of this 
obscure group. This ammonite has prominent umbilical tubercles and a 
few widely spaced low, rounded, coarse ribs, and the marginal tubercles 
are lacking. In these respects it agrees with Neolobites, but is thicker, 
more discoidal, has a more rounded keel, a more open umbilicus, and the 
suture consists of three saddles and two lobes, the first saddle being much 
taller and broader than the second. It will be seen that the suture has 
fewer elements than in Neolobites, and in this respect is like Flickia. The 
suture resembles that of Flickia in the simplicity, the roundness and the 
non-angularity of its elements; it differs in having the siphonal lobe 
broader and its sides more convergent towards the tip, the first lateral 
lobe shorter than the siphonal lobe, and the first lateral saddle much 
broader than the siphonal lobe. It differs from Flickia simplex and 
F. boesei in having ribs and umbilical tubercles instead of being smooth. 
The sutures on this ammonite are more numerous and crowded than in 
either genus mentioned. Due to lack of literature, a more exact generic 
determination can not be given. 

1 Ibid., Pervinquiere, p. 214, fig x 82. 

88 University of Texas Bulletin 

HORIZON: Top of lower half of the Del Rio clay, equivalent of Gray- 
son formation (top of zone of Exogyra arietina, in association with 
Turrilites bosquensis, Acanthoceras worthense, Pecten subalpinus, Gryphea 
mucronata) . 

TYPE LOCALITY : West bank of the South Bosque River, 150 yards 
south of the bridge on the Speeglevilte road, tall Del Rio cliff; 5.5 miles 
west of courthouse at Waco, Texas. 

DESCRIPTION : Form inflated, section of volution rather tall, flanks 
and venter broadly rounded, keel absent, dorsum concave with a sharper 
curvature than the venter ; volution covering about one-third of preceding 
one. Volutions with few widely spaced, very large, smooth, low umbil- 
ical tubercles each one-third to one-half the height of the volution; from 
each of these a single low broad rib runs ventrally, reducing in height 
and disappearing at the ventro-lateral margin. Ventral marginal tubercles 
absent. Umbilicus wide. Only three volutions visible in the type (in- 
terior damaged). The form is approximately that of Flickia boesei ex- 
cept for the presence of ribs and the much more open umbilicus. In the 
type the crowded sutures end abruptly near the end of the last volution, 
beyond, which the living chamber has several oblique low ribs each term- 
inating in a low, indistinct umbilical tubercle. 

SUTURE: In form the suture is rather like that of Flickia or of 
Neolobites, with a slight angularity in some places. Three lobes and three 
saddles visible on each side, including the siphonal lobe. Siphonal lobe 

Fig. 10. Flickia (?) bosquensis n. sp., diagrammatic projection of sutures of type 
individual, camera lucida drawing, x 5. 

subquadrate in outline, with two equal, simple, rounded lobules and a 
shallow external saddle. First lateral saddle about one and two-thirds 
times as broad as the siphonal lobe, more angular on its ventral margin, 
more evenly curved dorsally. First lateral lobe about half as broad as 

Weno and Pawpaw Formations 89 

first saddle, lower than first saddle or siphonal lobe. Second saddle still 
lower, about one and a half times as tall as the first lobe. Second lobe 
nearly as broad as second saddle, and somewhat lower. Most of third 
saddle visible externally, lying entirely on steep umbilical wall. Further 
elements of suture concealed by overlap on next inner volution. All su- 
tural elements are simple and entire, as in Flickia. 

PI. 1, fig. 14 

MEASUREMENTS: (Type individual). 
Height of volution, 8.0 mm. 
Width of volution, 4.7 mm. 

HORIZON : Base of Pawpaw formation, clay phase. 

LOCALITY : 723 (type locality) ; 714, both on Sycamore Creek, near 
Fort Worth, Texas. The species is rather rare; only a few fragments, 
most of them crushed, have been found. 

The genus Schloenbachia Neumayr, in the restricted sense adopted by 
de Grossouvre, Pervinquiere and others, includes ammonites with sinuous 
simple or branched ribs, umbilical and marginal tubercles, and sutures 
with the first lateral lobe usually trifid. Mortoniceras on the contrary 
usually has a square cross-section, coarse, almost straight, tuberculate ribs 
and the suture less dissected than in Schloenbachia, with the first lateral 
lobe more or less square and bifid. The type species are Mortoniceras 
texanum (Roemer) and Schloenbachia varians (Mantell). A rather rare 
pyritic species of the Pawpaw clay is here described on account of its 
stratigraphic importance. 

DESCRIPTION: Form discoidal, volutions rather flat and broad 
moderately embracing, outer volution covering about one-third the width 
of the preceding one, umbilicus therefore wide and open and, on account 
of the flatness of the volutions, rather shallow; three coils only exposed 
in the type (fragment), the two inner ones being practically smooth, the 
outer one decorated with numerous, closely spaced, low, evenly rounded, 
sigmoidal, branched and simple ribs, most of them having distinct, sharply 
elevated umbilical tubercles, which are nearly of even height and evenly 
spaced around the inner margin of the volution ; and near the ventral 
margin a low overturned, sharp-topped, oblique ridge representing the 
twin marginal tubercles. On this ridge the more dorsally situated tubercle 
is represented by a gently curved elevation and the more ventral tubercle 
is sharper-topped and descends abruptly by a steep ridge and becomes 

90 University of Texas Bulletin 

obsolete at a point near the keel, leaving practically no groove bordering 
the keel. The ribs, on this ridge, have sigmoidal flexures directed for- 
wards, while at the umbilical margin the ribs are directed backwards. 
The keel is sharp-topped, triangular in section, and elevated above the 
level of the lateral tubercles. The section of the volution is rectangular 
and slightly broader dorsally. At the widest point on the volution its 
height and breadth are in the ratio of 3 :2. The section is thus truncate- 
cuneiform; the flanks are practically straight, the venter lightly arcuate, 
and the dorsum has a V-shaped excavation for the reception of the next 
inner volution. 

PI. 3, figs. 8-11 

1920: Sehloenbachia sp. M, Adkins and Winton, Univ. Texas Bull. 1945, p. 34, pi. 5, 

figs. 1-4. 
1920: Sehloenbachia sp. M, Winton and Adkins, Univ. Texas Bull. 1931, p. 22. 

MEASUREMENTS : ( Type individual ) . 

Greatest height of last volution 34 mm. 

Greatest breadth of last volution, excluding tubercles 32 mm. 

Greatest diameter of shell . 104 mm. 

HORIZON: Upper Weno formation, shale and limestone facies, and 
ironstone bands in the blue shale of the Red River region. Known also 
from south-central Texas. 

LOCALITIES: 601, clay-ironstone layers in blue shale of upper part 
of Weno formation, pit of brickyards, one and three-fourths miles south- 
east of Gainesville, Texas (type locality) ; 604, cut of Frisco track, three- 
fourth mile north of Union Station, Denison, Texas; 612, 618, 714, 715, 
716, near Fort Worth, Texas ; 720, 721, near Riovista, Texas. 

DESCRIPTION: Shell discoidal, volutions thickened, umbilical wall 
steep, passing onto the flank by a rounded curve. Venter truncate, keel 
low with a parallel groove on each side. Flanks slightly convex between 
the ribs. Cross-section of volution subquadrate, slightly wider dorsally 
than ventrally. Flanks ornamented with ribs, each connected with a ven- 
tro-marginal tubercle. These ribs are either simple or bifid. The simple 
ribs disappear dorsally before reaching the umbilical angle. The bifid 
ribs end dorsally in a single, very tall umbilical tubercle and ventrally 
in two less elevated marginal tubercles. 

Visible portion of suture consists of siphonal lobe, two lateral saddles 

Weno and Pawpaw Formations 91 

and two lateral lobes. The siphonal lobe is about twice as tall as broad, 
and laterally is minutely dissected, and has also two or three prominent 
lateral inflections. The terminal points are slender and slightly incised 
laterally. The first lateral saddle is nearly twice as broad as the siphonal 
lobe and is trifid, having the more dorsal division slightly dissected, the 
broader central division trifid, and the slender ventral division next to the 
siphonal lobe entire. The deepest incision in the saddle lies between the 
first two divisions. The first lateral lobe is slender and about two and 

Fig. 11. Schloenbachia, wintoni n. sp., type individual, last suture, camera lucida draw- 
ing, x 5. Keel region slightly distorted in type individual. 

one-half times as tall as broad. It is bifid terminally and the ventral 
lobule is larger. Each lobule is trifid. The selond saddle is lower and 
broader than the first lobe, and is bifid terminally; laterally it has an ir- 
regular outline. The second lobe is broad and bifid. The internal suture 
has not been examined. 

This species differs from Schloenbachia nodosa Bose and S. trinodosa 
Bose in its suture and in the cross-section of the volution ; it differs from 
the common Schloenbachia of the Fort Worth limestone (S. leonensis of 
various authors) in many respects, notably in its marginal tubercles. 


PI. 1, figs. 6-10, 18-19, 26 
1920: Mortoniceras sp. Winton and Adkins, Univ. Texas Bull. 1931, p. 68. 


Fragment, outer whorl ; length 15.0 16.5 14.4 10.8 

Small end, height 3.5 4.3 3.0 2.4 

92 University of Texas Bulletin 

Small end, width 4.0 4.0 4.0 3.1 

Large end, height 4.5 5.5 5.3 4.0 

Large end, width 4.3 4.8 4.7 3.6 

HORIZON: Basal two-thirds of the Pawpaw formation, clay phase. 

LOCALITY : 723 (type locality) ; 714, and other localities near Fort 
Worth, Texas. 

DESCRIPTION: Shell discoidal, volutions slightly embracing, each 
covering one-fourth or less of the next inner volution, umbilicus conse- 
quently broad, volutions strongly ribbed with widely spaced, coarse, short, 
simple or bifurcated, straight ribs, each with an umbilical tubercle and a 
pair of coarse marginal tubercles which are connected by a concave topped 
ridge. These tubercles are abruptly raised above the level of the venter, 
but the oblique rapidly diminishing rib passes from the tubercle towards 
the keel and becomes obsolete; the keel is therefore bounded on each side 
by a narrow valley. Keel prominent, steep sided, triangular in section, 
taller than the outer ventro-lateral tubercle in the earlier volutions, lower 
in the later ones. Cross-section of the volutions roughly square, but in 
a few individuals even broader 1 than tall ; to be more detailed, the flanks 
are inflated, and in the region of a rib bicarinate, corresponding to the 
umbilical and lateral tubercles; venter tricarinate, corresponding to the 
keel and the two ventro-lateral tubercles; dorsal midline with a slight 
excavation, into which the next inner coil fits. Number of volutions six 
or more. At the 6 mm: stage (about four volutions) the shell is prac- 
tically without ribs. The ribs then come in as straight, broad, low, wedge- 
shaped elevations, thicker and higher at the marginal end, where the 
pair of marginal tubercles is an elongate prominence with a slight tuber- 
culate swelling at each end. Within the next half volution the umbilical 
tubercles have become prominent, and the marginal tubercles are as tall 
as the keel, giving to the cross-section of the volution a nearly square 
aspect, instead of the triangular section which exists in the younger stages, 
in which the keel is still prominent. The sutures coincidently increase in 

SUTURE : The siphonal lobe is nearly quadrate. It is bifid and each 
lobule is relatively simple. The first saddle is broad and is twice bifid. 
The remainder of the suture is invisible on the flanks of the individuals 
at hand, which are preserved as pseudomorphs of coarse grained hematite 
which has replaced all structures and destroyed the details. From the 
ends of fragments broken along suture lines it is inferred that the first 
lateral lobe is lower than the first saddle and about two-thirds as broad; 
terminally it is divided and possibly is trifid. The second saddle is lower 

Weno and Pawpaw Formations 93 

and narrower than the first lobe, and apparently is bifid; it lies at the 
level of the dorso-marginai tubercles. The second lobe lies on the um- 
bilical wall and is broad and flat, but from the material at hand its de- 
tails can not be described. Between it and the tall narrow anti-siphonal 
lobe there is a depressed saddle-like space. This description and figure 
of sutures are taken from the individual figured on plate 1, figure 6. 

Fig. 12. Mortoniceras worthense n. sp., suture of individual, Plate 1, Figure 6, camera 
lucida drawing, x 10. 

This species has similarities to Mortoniceras inflatum var. spinosum 
Pervinquiere 1 (Vraconian of Tunis). One individual of five volutions 
has two gaps in the ribbing of the last volution; they have no obvious 
relation to the branching or doubling of ribs. The same feature is noted 
in the earlier volutions in this species. 


PI. 1, figs. 11-13, 16-17, 20-25 
1920: Acanthoceras sp. Winton and Adkins, Univ. Texas Bull. 1931, p. 69. 

MEASUREMENTS : PI. 1, fig. 12 PI. 1, fig. 13 

Type (I) II 

Greatest diameter 14.9 mm. 13.8 

Height of last whorl 6.0 mm. 6.0 

Width of last whorl 6.0 mm. 5.0 

Width of umbilicus 1.4 mm.(?) 1.0 

HORIZON: Pawpaw formation, basal two-thirds, clay facies. 

LOCALITY: 723 (type locality), near Fort Worth, Texas; 714, 715, 
716, 719, 724, near Fort Worth, Texas. The species is generally abundant 
in favorably weathered exposures of the clay phase. 

DESCRIPTION: Shell discoidal, compressed, four or more volutions 
considerably embracing, umbilicus consequently small ; shell keelless, sec- 

'Et. pal. tun., p. 229, pi. xi, fig. 3a-b. 

94 University of Texas Bulletin 

tion of volution roughly oval, venter smooth in young individuals and 
very slightly convex. In older individuals, however, there is a median 
broad, low, very rounded swelling, similar to a median tubercle. In young 
individuals the ribs become obsolete just ventral to the ventral marginal 
tubercle, but in older individuals the ribs are continuous across the venter. 
Ventro-marginal tubercles acute, one on each rib, becoming obsolete in 
the later volutions. Ribs long and short, mainly unbranched. Dorso- 
lateral (umbilical) tubercles few and scattered. Cross-section of earlier 
whorls subrectangular, flanks straight, venter lightly convex, dorsum very 
concave; in later whorls the flanks are more rounded and make an even 
curve with the venter. In certain young individuals the ribs are flexuous, 
having a prominent sigmoidal curve, and are much thickened at the mar- 
ginal tubercle. This individual shows no ribs at a diameter less than 
3.8 mm. After that diameter, the intercalated ribs, one or two between 
some branches, are similar to those of the later volutions. 

The suture of the species resembles that of young individuals of 
A. martimpreyi Coquand, as figured by Pervinquiere. 1 The considerable 

Fig. 13. Acanthoceras worthense n. sp., suture, camera lucida drawing, x 8. 

amount of material at hand does not contain any sutures which are much 
more complicated than the ones figured here. The suture shows exter- 
nally besides the siphonal lobe, four saddles and four lobes, which pro- 
gressively decrease in size toward the anti-siphonal region. The bifid 
first saddle is more irregular and less square than in the examples of 
A. martimpreyi mentioned. All the remaining saddles are simple, or 
bifid, and the lobes are generally bifid. The first lobe is as tall as the first 

iPervinquiere, Et. pal. tun., p. 294, figs. 109-110. 

Weno and Pawpaw Formations 95 

saddle and about three-fourths as broad. The second and third saddles 
are taller than broad and rather angular in form. The remaining lobes 
likewise are subquadrate and shallowly bifid. The internal suture has not 
been examined. 

This species greatly resembles Acanthoceras martimpreyi Coquand 
A. aumalense Coquand, and A. suzannae Pervinquiere, all from the Vra- 
conian of Tunis. 


The genera of Comanchean starfishes are in such great need of defini- 
tion that it has been found impossible to assign the Texas species with 
much certainty to the proper genera ; for in the absence of authentic ma- 
terial of described species it is difficult to make such definitions fron< 
figures and text alone. When the Texas starfishes are closely defined it 
will probably be necessary to form new genera for certain of the species, 
but in the meantime they have been provisionally assigned to known 
genera, avoiding when possible those founded on recent species, on ac- 
count of the great amount of subdivision which the recent Asteroideo 
are receiving at the hands of modern workers. 

PI. 7, fig. 7 

1920 : Pentagonaster texensis Adkins and Winton, Univ. Texas Bull. 1945, p. 47, pi. 10, 

figs. 5-6. 
1920: Pentagonaster texensis Winton and Adkins, Univ. Texas Bull. 1931, p. 22. 

A recently discovered individual shows the superomarginal plates, and 
the interior of the disk is eroded down to the oral surface, of which several 
adambulacral, circumoral, and a few paramarginal plates are exposed. 
All of the superomarginal plates are shown, but due to erosion and the 
thinness of the disk, certain oral plates come into view, and there is over 
the disk a resulting mixture of oral and aboral plates. This individual 
was found in a limestone slab, face down, at the type locality described 

HORIZON : Upper five feet of the Weno limestone. 

LOCALITY: 602, east slope of the valley of Sycamore Creek, four 
miles southeast of Fort Worth, Texas, at a level 29 feet below the base 
of the Mainstreet limestone. 

96 University of Texas Bulletin 


SUPERO-MARGINAL PLATES: On each aboral interarc there are 
fourteen supero-marginal plates excluding the terminal plate, which is 
common to each two adjacent arcs. These plates, though separated, seem 
well preserved, and in this individual as in the type, lack ornamentation. 
It is entirely possible that better material will show superficial structure 
on the plates since most related species show it. In shape the plates are 
trapezoidal or cuneiform, as described for the type. They are tallest 
and widest at the center of the arc and decrease in size to the tips of the 
rays. The marginal plates of this species are relatively large and are 
taller than broad ; in Pentagonaster browni Weller, they are broader than 
tall, and are relatively smaller. 

PARAMARGINAL PLATES : These are a row of minute, nearly equal 
and similar subquadrate plates lying apposed to the inner edge of the 
marginal plates. Only a few, near the tips of the rays, are preserved in 
this individual; they apparently belong to the aboral surface. 

ADAMBULACRAL PLATES : These plates, as described in the type, 
are mostly quadrate and are of about the same size as the other interior 
oral and aboral plates (about .5 mm. diameter). This individual has 
along one radius two nearly apposed rows of plates that belong to this 
class; they diminish in size somewhat toward the tip of the ray. 

CIRCUMORAL PLATES: There is a group of plates massed around 
the mouth region, which are in part oral plates and in part dislocated 
central aboral plates. They are rounded and larger than the other interior 
plates, and a few are elongate. In the absence of better material, they can 
not be described more accurately. 

INTERMEDIATE PLATES : There are a few continuous radial rows 
of plates lying on the radii and extending from the center of the disk to 
the tips of the rays. These are apparently aboral plates. They have a 
rounded, roughly quadrate to hexagonal shape, and are small, equal and 
similar. The madreporite and ambulacrai details are not visible. 

RELATED SPECIES : Pentagonaster browni Weller (Fox Hills form- 
ation, Lander, Wyoming) is described as having 16 supero-marginal plates 
which are relatively smaller and less tall than in this species. The inter- 
radial arcs of the Wyoming species are also deeper than in our material. 
P. lunulatus Woodward and P. megaloplax Sladen (Upper Chalk, Senonian) 
differ from the Texas species in having punctate or papillose marginal 
plates, in the concavity of the interarcs, and in the number of marginal 
plates. P. robustus Spencer (Upper Chalk) differs in the same charac- 
ters and in the meeting of the supero-marginal plates along the midline 

Weno and Pawpaw Formations 97 

of the ray; and P. obtusus Forbes (Upper Chalk) is stated to have 18 
marginal plates, the superior ones punctate and the two sets alternating. 

I (type) II 

R (average of five) 23.5 mm. 15.9 mm. 

r (average of five) 14.8 mm. 9.9 mm. 

R/r 1.58 1.6 

PI. 7, fig. 6 

1920: Metopaster hortensae Adkins and Winton, Univ. Texas Bull. 1845, p. 46, pi. 10. 

figs. 2-4. 

1920: Metopaster sp. Winton and Adkins, Univ. Texas Bull. 1931, p. 69. 
1920: Metopaster hortensae Winton and Adkins, ibid., p. 21. 

This rare species, which characterizes the basal Pawpaw clay, has very 
tuberculated and spiny plates. The marginals are covered with closely 
set, low, rounded tubercles, and at places have adherent clumps of small 
thick spines. 

One row of ambulacral pore plates is shown on the type individual. 
This has two rows of oblique pores, indicating four rows of tube-feet per 

As already stated, there are six paired supero- and infero-marginals in 
addition to the terminal unpaired supero-marginal plate, totalling eight 
supero-marginals and six infero-marginals. 

The terminal marginal plate is similar to that of Mitraster, which differs 
from the Texas form in its cycloid contour and in the shape and ornamen- 
tation of its marginal plates. 


PI. 7, figs. 4-5 
1920: Comptonia sp. Adkins and Winton, Univ. Texas Bull. 1945, p. 49, pi. 10, fig. 1. 


Major radius, about 24 mm. 

Minor radius (average) 6 mm. 

DESCRIPTION: Disk flat although somewhat collapsed in the type. 
Rays elongate, tapering, incomplete in the type; probably the ratio R:r is 
about 4:1. Minor radius about 6 mm. in the type. Supero-marginal and 
infero-marginal plates numerous, usually paired, disk relatively small and 

98 University of Texas Bulletin 

the interradial arcs next to the disk paraboloid, sharply instead of broadly 
curved, and in this respect more similar to Comptonia comptoni Forbes 
than to C. elegans Gray. The two rows of supero-marginal plates are 
apparently nowhere in contact throughout the length of the ray. Oral 
and aboral sides of disk covered with rather small, unequal, polygonal to 
rounded raised plates. 

ABORAL SIDE : The supero-marginal plates at the center of the arc 
are slightly wedge-shaped with rounded interior margins ; their sides con- 
verge slightly, passing out from the center of the disk. The plates de- 
crease in size and are more elongate, on approaching the tip of the ray. 
Over the central part of the arc seven plates have the breadth of about 
10 mm. There are probably about 20 supero-marginal plates in one entire 
arc (the tips of the rays are absent in the type) . 

Along the center of each ray is a row of radial plates which are larger 
than the other central plates but not elevated above them. One elevated 
rounded plate on each interray bears a small circular pore (gonopore). 
In one interray there are two such plates. Between these plates are more 
depressed rows of plates arranged so as to make a pentagon with its cor- 
ners at the interradii. The central radial rows of plates along the rays 
meet the middles of the sides of this pentagon. The small, raised, oval 
madreporite is situated excentrically, and bears 9 or 10 radiating mostly 
divaricate, V-shaped straight ridges. 

ORAL SIDE : The infero-marginal plates are equal in width and in num- 
ber to the supero-marginal and lie opposite them or nearly so. The oral 
surface of this starfish is distinctly broader than the aboral surface, so 
that the line of junction of the two sets of marginals is situated well aboral 
to the edge of the disk (and this does not seem to be due to crushing). 
The infero-marginal plates are subquadrate-cuneiform in profile, but are 
very thick and rounded at the external edge. No para-marerinal rows of 
plates are visible. The other plates of the oral face of the disk, which 
are poorly preserved, are also not in rows. The five ambulacral grooves 
are distinct but without perceptible structure in our material. The num- 
ber of rows of tube feet is unknown. The grooves are prominent, and 
have near the peristome a breadth of about .6 mm. The marginal and 
other larger plates are covered by rather fine, low, round, irregularly 
scattered tubercles. Evidences of spine pits and pedicellariae are absent. 

The species differs from Comptonia elegans Gray in several noticeable 
features. The disk is practically flat in our species; it however, shows 
some evidence of flattening in preservation, since the central plates are 
considerably and abruptly depressed below the level of the supero-marginal 

Weno and Pawpaw Formations 99 

plates. Comptonia elegans on the other hand has a central ridge of very 
rounded elevated plates running the length of each ray and connecting 
to form on the disk a central, narrow, elevated ring. In our species the 
center of the disk is flat and the plates are very little disarranged, since 
the depression mentioned above has not disturbed the relations of the 
central plates to each other. 

Calliderma and Nymphaster differ from our species in many notable 
features. Both have the aboral interadial areas in most species confined 
to the disk, so that the supero-and infero-marginal plates meet over most 
of the length of the ray. This is not true in the Texas species. Both 
genera named were described from recent species, the genotypes being 
Nymphaster protentus Sladen 1 and Calliderma emma Gray. 2 

This species differs from Comptonia elegans Gray in several important 
respects. The disk is practically flat in our species; it, however, shows 
some evidence of flattening in preservation, since the central plates are 
considerably and abruptly depressed below the level of the supero-marginal 
plates. Comptonia elegans, on the other hand, has a central ridge of very 
rounded elevated plates running the length of each ray and connecting 
to form on the disk a central narrow elevated ring. In our species the 
center of the disk is flat and the plates are very little disarranged, as the 
foregoing description shows. 

PI. 7, figs. 1-3 

MEASUREMENTS: R (average of two) 45.0 mm. 

r (average of five) 10.4 mm. 

R:r 4.33:1 

A species having the form of Pentaceros jurassicus Quenstedt and in 
most respects agreeing with the described generic characters, is here re- 
ferred to this genus. 

HORIZON: Base of the Pawpaw formation, clay fades, 
TYPE LOCALITY: 714, one-fourth mile south of the International 
and Great Northern Railway bridge across Sycamore Creek, four and 
one-half miles southeast of Fort Worth, Texas. One individual, the type, 
was found here. 

Sladen: Narrative of Challenger Exp., 1886, vol. 1, p. 612; Zool. Chal. Exp., part li, 
Report on the Asteroidea, 1889, p. 294. 

Fisher, W. K., Starfishes of the Philippine seas and adjacent waters. U. S. N. M. 
Bull. 100, vol. 3, p. 261, 1919. 

2 Gray: Proc. Zool. Soc. Lond., part XV, 1847, p. 76; Ann. Mag. Nat. Hist., 1847 
vol. XX, p. 198; Synopsis of Species of Starfish, British Museum, 1886, p. 7. 

100 University of Texas Bulletin 

TYPE INDIVIDUAL : A well preserved individual showing both sides 
of the disk in great detail and having two complete and three fragmentary 
rays. Museum of Texas Christian University, Fort Worth, Texas. 

DECRIPTION : Marginal plates distinct, subrectangular on edge 
view, rounded on the face, bearing fine tubercles. Inter-marginalia pres- 
ent in the interarcs and the proximal half of the rays, decreasing in size 
outwards from the disk. Disk relatively small, arcs sharply rounded, rays 
long and slender; oral surface flat with numerous small plates; aboral 
surface with a central raised pentagonal system of plates and a row of 
radiating plates on the midline of each ray. 

ABORAL SIDE : The rays are slender and the interarcs sharply 
curved. Each interarc contains from tip to tip of the rays 48 supero- 
marginal plates (17+7 in each half arc) . Of these all except the terminal 
seven of each ray are elongate in the direction of the ray, sharply rounded 
on top and separated from those of the opposite side of the ray by radial 
plates. The terminal seven plates of each margin of the ray are apposed 
along the mid-line; the plates are transversely elongate and join by alter- 
nate facetting, along a zigzag line; the terminal plate is unpaired and 
is common to the two rows. The seven terminal plates are swollen and 
smooth and present a very different appearance from the others. In the 
type they are smooth and whitish, lacking the iron stain of the rest of 
the animal. A single row of radials extends from the inner pair of these 
terminal plates to a polygonal elevation in the center of the disk, the plates 
increasing in size towards the disk. Between this row of plates and the 
supero-marginal plates there are two parallel rows of plates, an adradial 
row of large plates fitting into the spaces between the radialia, and a 
para-marginal row of small cuboidal plates lying against the marginal 
plates, there being about three of these plates to one marginal plate. 

The interradial areas on the disk are triangular and are covered with 
three or four rows of small plates lying close to the marginals; at the 
apex of each area is a perforated, elevated polygonal plate, the genital 
plate with its gonopore. The radial ridges running on the mid-line of 
the ray near the disk are composed of three irregular rows of large rounded 
ossicles and numerous smaller scattered plates, which were apparently 
imbedded in a membrane. The central polygonal ring-like elevation at 
their union bears scattered large and small ossicles. The anus is sub- 
central and large ; the madreporite is excentric, raised, hexagonal in shape, 
depressed in the center, and has coarse imbricated V-shaped ridges, and 
straight, simple or branching ridges, radiating from the center. 

ORAL SIDE : The oral side is strikingly flattened, being only slightly 
compressed along the ambulacral grooves. Its prevailingly smooth ap- 

Weno and Pawpaw Formations 

pearance is due to the smallness and flatness of the numerous ptales: #hi(5h 
make up its area. Infero-marginal plates as described for the supero- 
marginals, and paired with them; however, there are only six inflated 
terminal plates separated to the tip of the ray by the ambulacral groove: 
The common terminal closing plate is restricted to the aboral side. Infero- 
marginal plates finely granulose. 

Interambulacral areas of oral side broadly triangular with numerous 
crescentic, coarsely granulated small plates in roughly concentric rows. 
An adambulacral row of plates with combs of spines lies next to the 
ambulacral grooves. Between these and the marginals is one row of 
plates over most of the length of the ray, but on approaching the inter- 
radial areas other rows enter. Peristome central, apparently protected 
by fine incurved spines. 

The species resembles in form Nymphaster radiatus Spencer (Lower 
Chalk, Upper Cenomanian), from which it differs in the shape and orna- 
mentation of its marginal plates. It also has resemblances to Pentaceros 
boysii Forbes and P. squamatus Forbes, both from the Upper Chalk of 
Kent, England (Senonian), but it differs in these in its form and in the 
ornamentation of the plates. 



Cidarids are known from all the Texas Washita formations above the 
Fort Worth limestone. These are undescribed and their tests and spines 
unrelated with one exception, Leiocidaris hemigranosus Shumard from 
the Denton formation, of which spines and test have been found in such 
close proximity that they almost certainly belong to the same animal. 
Cidarid plates, apparently of a Leiocidaris, are abundant in the Quarry 
limestone group of the Red River region and with them occur great num- 
bers of spines. In addition, in the Pawpaw clay and in the Grayson marls 
there are several different species of large cidarid spines. In the Main- 
street limestone well preserved cidarid tests are known. 

Cidarid sp. 1, spine: The commonest echinoid spine of the Quarry group has the 
following characteristics : 

The shaft bears about sixteen carinae which are made up of rows of rounded, bead- 
like tubercles, whose tips are slightly pointed down the shaft. The rows are even 
topped and depressed. On some spines certain carinae are elevated considerably above 
others and are longer, more prominent, and have a sharp serrate keel and a triangular 
cross-section. The spine is a short oval in cross-section. Below the tip of the shaft 
several, in part alternate, carinae end, and the remaining ones become more elevated 

102 University of Texas Bulletin 

p.nd- sharp keeled, .giving to the shaft a Cereus-like appearance. At the base of the 
spine there is an inflated sharp topped milled collar; the condyle is constricted and the 
articulating surface deeply excavated. Locality: 601, near Gainesville, Texas; widely 
distributed in North Texas. 

Cidarid sp. 2, spine: Cidarid spines of medium length, the shaft not inflated. The 
shaft bears about 30 depressed, even topped, equal and equally spaced continuous lines. 
The base is gently inflated and straight sided down to the collar. The collar is not 
milled and is rounded, making a wide angle with the shaft. The straight margin of 
the base below the collar descends to the rim of the circular articulating socket. This 
spine differs from the preceding in having numerous nonserrate carinae. Locality: 
601, pit of brickyards, near Gainesville, Texas. 

Cidarid sp. 3, spine: Spines with an inflated, club-like shaft bearing about 10 
sharply but unequally elevated, smooth keeled carinae and a prominently constricted 
neck. The margins of the base above and below the collar are smooth and straight 
and make at the collar a rounded angle of about 135 degrees. The rim of the cir- 
cular articulating socket is a ring-like thickening. Cross section of inflated shaft ang- 
uJar and subcircular. Locality: 601, pit of brickyards near Gainesville, Texas, Quarrj 


A species of Gonipygus from the basal five feet of the Pawpaw forma- 
tion clay facies, locality 714, near Fort Worth, Texas, is in the hands of 
Professor F. L. Whitney for description. 


1893: Dumblea symmetrica Cragin, Geol. Surv. Texas, 4th Ann., Kept., p. 150, pi. xxiv, 1 

fig. 12; pi. xxv, figs. 4-7; pi. xxvii, fig. 1. 
1915: Pedinopsis symmetrica Clark, U. S. G. S., Mon. LIV, p. 64, pi. xxiii, figs. 1 a-h 

Three individuals of this species found in the basal Weno marl, locality 
618, near Fort Worth, Texas, have been placed in the hands of Professor 
F. L. Whitney for description. 


A poorly preserved individual somewhat similar to a Peltastes found 
in the topmost stratum of the Mainstreet limestone at Denison, Texas, 
was found at locality 714, near Fort Worth, Texas, in the basal stratum 
of the Pawpaw clay, and it is referred to this genus. These echinoids 
will be described by Professor F. L. Whitney. 

Erroneously cited as pi. xxxiv by Cragin and Clark. 

Weno and Pawpaw Formations 103 


A large flattened Salenia, resembling in form S. mexicana Schltiter, 
which is not known to range so high, was found in the basal stratum of 
the Weno formation, just on top of the Gryphea washitaensis shell con- 
glomerate of the Denton marl, by the St. Louis and San Francisco Railway 
track, two and one-half miles north of Denison, Texas. 

The following are some of the features of this individual: There are 
about 20 pairs of ambulacral tubercles, obliquely situated ; the ambulacral 
lips are considerably wider than the inter-ambulacral lips ; the apical sys- 
tem ("cap") is large, the plates ornately scalloped; the sutures are widely 
and irregularly excavated. . ^ 

Salenidae have so far been found at the following levels in the Texas 
Comanchean : 

Buda: S. volana. 

Grayson: Peltastes sp.: Goniophorus sp. 

Mainstreet: . 

Pawpaw: Peltastes? sp., Salenia volana. 

Weno: Salenia sp. aff. texana. 

Denton: Goniophorus sp. 

Duck Creek marl: Goniophorus sp. 

Duck Creek limestone: Salenia sp. 

Goodland limestone: Salenia mexicana, S. texana, Salenia n. sp. 

Walnut: S. mexicana; S. n. sp. 

Glenrose: Salenia n. sp. 


This widespread Upper Washita species is occasional in the Weno form- 
ation, marl facies, in association with a considerable echinoid fauna and 
other fossils, such as Turritella worthensis, Venericardia worthensis, 
Remondia ? acuminata and Ancycloceras bendirei. It is known otherwise 
from the Weno to the Buda limestone. 


This species is distinguished from Holectypus planatus Roemer by hav- 
ing the periproct in length about half the radius of the test and situated 
about halfway between the centrally located peristome and the ambitus, 
while the Holectypus planatus the periproct occupies almost the entire 
length between the peristome and the ambitus. This species, described 
from subdivision 5 of Cerro de Muleros (Duck Creek and Fort Worth 
formations) occurs in the Upper Washita beds of North Texas as 

104 University of Texas Bulletin 

Holectypus planatus does in the Lower Washita and Fredericksburg beds. 
It is scattering in the Weno and Pawpaw formations but more abundant 
in the echinoid horizon at the base of the marl phase of the Weno forma- 
tion, in association with Enallaster bravoensis, E. wenoensis, Hemiaster 
riovistae, Epiaster wenoensis, Pedinopsis symmetrica and Holaster. It is 
sparse in the Mainstreet formation and has a zone of abundance near the 
base of the Grayson marl. 

HOLASTER sp. aff. SIMPLEX Shumard 

HORIZON: Weno formation, marl facies, abundant near base; Paw- 
paw formation, marl facies, occasional near top. 

LOCALITIES: 611, 612, 618, 715, 716, 718, near Fort Worth, Texas; 
721, 722, near Riovista, Texas; cut of Missouri, Kansas and Texas Railway, 
one mile north of Union Station, Denison, Texas, between localities 605 
and 606. 

The common Holasters of the Weno and Pawpaw formations have close 
similarities with the low phase of Holaster simplex Shumard of the Duck 
Creek and Fort Worth formations, but are specifically distinct. How- 
ever, it is considered best to defer their description awaiting better ma- 
terial. These echinoids occur as eroded mud-filled, calcite tests and the 
ambulacral areas and apical system are almost invariably damaged. 

Tests ovoid in outline, non-angular, anterior notch shallow, longer than 
tall, greatest perimeter generally above the base. 

Ambulacra flush with surface, postero-laterals in some individuals more 
divergent than in H. simplex; peristome transverse, oval, lying in a de- 
pressed space near the ambitus. Peripcroct low, ovoid, vertically elongate 
lying in tall individuals beneath a prominent posterior median projection. 
Apical system subcentral elongate. 

It should be borne in mind that the Holasters of the Weno marl are 
diverse, and that among them Holaster simplex may occur, since its known 
stratigraphic range extends into the upper Fort Worth limestone. 

The species of Holaster closely related to H. simplex Shumard of the 
Duck Creek and Fort Worth formations, and found in the Weno and Paw- 
paw formations shows the same variation in form as the lower species; 
sloping individuals with their greater perimeter at the base, and top-heavy 
individuals with the greatest perimeter above the base, are common, the 
latter being most abundant. This species seems to differ from H. simplex 
in the shape of the madreporite which is elongate instead of subquadrate 
and in details of the apical system. Since such species are not easily de- 
finable by form alone, it has been thought advisable not to describe the 

Weno and Pawpaw Formations 105 

Weno species until more material is available. Cragin 1 described three 
species of Holaster, some of which are valid species. Holaster supemus 
Cragin (Grayson marl, Argyle, Texas), a top-heavy echinoid with a cir- 
cular apical system, is a Stenonia. The small low species, H. nanus, from 
the "Vola bed" (Mainstreet?) on the Denison-Bonham road, Choctaw 
Creek, Grayson County, Texas, is apparently the same low species that is 
common in the Weno and Pawpaw formations throughout North Texas. 
The other species, H. completus, which was found in the "Denison beds" 
and the Mainstreet limestone in Goyson County, has a very distinctive 
apical system, but has the periproct infra-marginal, and is not a Holaster. 
In addition, a very small pyritic Holaster whose characters are too im- 
perfectly known to warrant description, occurs in the basal Pawpaw clay. 


PI. 6, fig. 6 


Type: Length 54 mm. 

Breadth 50 mm. 

Height 29 mm. 

Apical system to posterior border 32.5 mm. 

HORIZON : Weno and Pawpaw formations, most abundant in the basal 
third of the Weno, marl facies, in association with Holaster sp. aff. simplex 
Shumard, Enallaster bravoensis Bose, E. wenoensis n. sp., Hemiaster cal- 
vini Clark and H. sp. aff. bexari Clark. 

LOCALITIES: 618, near International and Great Northern Railway 
track, three miles southeast of Fort Worth, Texas (type locality). 602, 
611, 612, near Fort Worth, Texas ; near Riovista and Blum, Texas ; three 
miles north of Gainesville, Texas; Missouri, Kansas and Texas Railway 
cut one mile north of Union Station, Denison, Texas; and elsewhere gen- 
erally distributed in the North Texas Weno. Localities 714, 715, 718, 723, 
and other Pawpaw localities near Fort Worth, Texas, especially in the 
upper marly portion of the Pawpaw. 

DESCRIPTION : Superficially similar to Hemiaster elegans Shumard, 
but smaller, smoother, less inflated, less bulged between the ambulacral 
grooves, and with straighter and narrower ambulacra. The species re- 
sembles E. aguilerae Bose, but is smaller and differs in the form and am- 
bulacral details. The Texas Comanchean Epiasters may be distinguished 

'Cragin, Geol. Surv. Texas, 4th Ann. Kept, pp. 165-168. ' 

106 University of Texas Bulletin 

from Hemiaster calvini and others by the absence of a conspicuous tubercle 
between the pores of a pair in the unpaired ambulacrum and usually by 
the larger size, the slighter depression of the ambulacral grooves, and the 
shape of the test. It is stated that Hemiaster has peripetalous fascicles 
while Epiaster lacks them ; but this character is of no value in the usual 
Texas material, which entirely lacks fascicles. Hemiaster elegans and 
Epiaster aguilerae are of large size, while Hemiaster whitei and Epiaster 
wenoensis are of medium and small size. 

Test: Inflated, rotund, smooth, ambulacra nearly straight, only slightly 
depressed. Widest point of test just anterior of apical system, tallest 
point on mid-line posterior to apical system and one-third the distance 
from it to the ambitus. Sides inflated, rather straight, greatest peri- 
meter at bottom. Aboral side nearly flat, peristome region excavated, 
with a projecting keel on the posterior lip and the grooves of the antero- 
laterals and the anterior sulcus slanting into the peristome. Posteriorly 
on the oral mid-line the test is inflated, the most prominent point being 
near the posterior end of the test. Ambitus rounded, with only an antero- 
lateral angulation just back of the point where the antero-lateral ambul- 
acra cross the ambitus; posteriorly the test has a rounded outline. Test 
narrowed to a pointed, very narrowly truncate posterior end. 

Unpaired ambulacrum lies in the shallow anterior sulcus, which is sim- 
ilar in form to the other ambulacral grooves, but slightly narrower. Each 
one has about thirty-one pairs of short slit-like pores set at a slight angle 
to each other. 

Antero-lateral ambulacra diverge at an angle of about 150 degrees, 
then turn forwards slightly, being thereafter almost straight to the am- 
bitus. Pore zones similar, with the pores almost equal. Each zone has 
about fifty pore pairs, the pores being short, slit-like, and not set at an 
angle to each other. Both pores of the anterior zone and the anterior 
pores of the posterior zone are equal ; the posterior pores of the posterior 
zone are about one and one-third times as long. 

Postero-lateral ambulacra long, straight, diverge at an angle of about 
60 degrees. About fifty-four pore pairs in each zone, pores slit-like, sim- 
ilar and nearly equal, the interior ones being, however, shorter than the 
exterior ones. 

Peristomal ambulacral pores. The ambulacra after crossing the am- 
bitus continue as smooth finely granulated strips of large plates with 
reduced pores, and end at the peristome. However, on approaching the 
peristome the pores become conspicuous and are borne on elevated knobs 
with a crater-like opening to one side of the top. These are present in 
the following Texas species examined : Epiaster wenoensis n. sp. (most 

Weno and Pawpaw Formations 107 

prominent), E. aguilerae Bose, Hemiaster elegans Shumard, H. whitei 
Clark, H. sp. ( Fredericksburg division), H. calvini Clark. The antero- 
lateral rows are conspicuous, consist of eight to nine cup-like elevations 
decreasing in size outwards from the peristome, the cavities opening out- 
wards and forwards in the anterior row, outwards and backwards in the 
posterior row. Each cavity bears two nearly circular ambulacral pores, 
placed obliquely. The antero-lateral and postero-lateral craters make two 
V-shaped rows at their junctions back of the peristome. The postero- 
lateral rows each contain about five similar, smaller craters which are 
lower and more widely spaced farther from the peristome. 

Peristome oval, the long axis transverse, the anterior curvature being 
even, the posterior margin with a central, bluntly rounded, elevated, for- 
wardly projecting lip. 

Periproct rather similar to that of Epiaster aguilerae Bose: shape 
trapezoid with the bottom and top rounded, the two superior angles being 
sharply rounded and the superior margin but slightly arched; the sides 
diverge, making the periproct broader at the bottom than at the top; 
the inferior angles are broadly rounded and the inferior margin likewise, 
it being nearly the arc of a circle of the same diameter as the periproct. 

RELATED SPECIES: Epiaster wenoensis n. sp. is smaller than 
E. aguilerae Bose; is more narrowed and pointed posteriorly; is less ele- 
vated medially just posterior to the apical system, but farther posteriorly 
is more straight-topped, the slope to the periproct being relatively abrupt ; 
the notch made in the ambitus by the anterior sulcus is shallower and less 
pronounced than in E. aguilerae; the peristomal ambulacral pores are 
larger and more pronounced, more numerous and more crowded than in 
any other Texas species examined ; the species is more smooth in appear- 
ance and more sparsely tuberculated aborally than E. aguilerae Bose or 
H. elegans Shumard. 

The relations existing between Hemiaster, Epiaster and Macraster in 
the Texas Comanchean have not been satisfactorily solved. Hill 1 and 
Clark- have considered Macraster texanus Roemer 3 to be synonymous with 
Hemiaster elegans Shumard. 4 Roemer and Bose 5 state that this species 
comes from the Fredericksburg division, but Hill 6 says that| it "makes a 
well defined horizon near the very top of the immense thickness of lower 

iHill, Annotated Check List, etc., Geol. Surv. Texas Bull. 4, p. 2, 1889. 

'Clark and Twitchell, U. S. G. S. Mon. LIV, p. 88, 1916. 

"Roemer, Neues Jahrb. f. Min., Geol. p. Pal., Bd. I, pp. 191-195. Tf. VI, 1888. 

'Shumard, Pal. Exp. Red River of La. in 1852, p. 210, pi. II, fig. 4a-c, 1853. 

5 B6se, Inst. Geol. Mex. Bol. 25, p. 173, 1910. 

"Hill, On the Occurrence of Macraster texanus, Amer. Nat., XXIII, p. 68, 1889. 

108 University of Texas Bulletin 

marine Cretaceous in Texas" (Buda limestone?) and is "not as Dr. 
Roemer infers from the specimens which accompanied it to Germany : 
with the Exogyra texana fauna, a statement which has been verified by 
Mr. George Stolley, the collector." 

The distinction between Hemiaster and Epiaster revolves around the 
presence or absence of fascicles, and Clark' refers Epiaster elegans Auctt. 
to the genus Hemiaster "as better material has shown that peripetalous 
fascicles are present although poorly developed and commonly destroyed 
on most specimens." There seems no a priori reason for doubting this 
statement until well preserved material demonstrates the contrary. 

Epiaster aguilerae Bose, 2 a distinctive species of the lower Fort Worth 
limestone, described from subdivision 5 of Cerro de Muleros near El Paso, 
is here redescribed by comparison with E. wenoensis n. sp., an analagous 
a'nd equally distinct species from the Upper Washita beds of North Texas. 
In the collections of the Department of Geology, University of Texas, is an 
unlabeled echinoid, probably an Epiaster wenoensis, and marked with 
a red T, as many of Cragin's types were marked, but whether this is a 
type, and of what, is unknown. Its dimensions, length 36.5 mm., breadth 
34.0 mm., height 17.0 mm., do not agree with those of any Epiaster men- 
tioned by Cragin, who described Epiaster electus (Travis Peak forma- 
tion), E. elegans var. praenuntius (Comanche Peak limestone), E. hem- 
iasterinus (Grayson formation), and E. whitei Clark (Travis Peak, 
Comanche Peak and Fort Worth formations). Since Cragin's species are 
unfigured and the types apparently lost, they are considered invalid species. 
The present species differs from Hemiaster whitei Clark in being much 
less tuberculate, in having narrow straight ambulacra in shallow grooves 
instead of wide ambulacra in deep grooves ; the form is much wider, more 
broadly rounded posteriorly, and distinctly lower; the slope anterior to 
the apical system is steeper. In appearance this species can not be con- 
fused with the common H. whitei Clark of the North Texas Goodland lime- 
stone. Epiaster hemiasterinus Cragin is considered by Clark 3 as identical 
with Hemiaster whitei, and Cragin admits 4 the "probable identity" of the 
two. It is described as being tall, with deep ambulacral grooves. 

iClark and Twitchell, U. S. G. S. Mon. LIV, p. 88, 1916. 

2 B6se, Inst. Geol. Hex., Bol. 25, .p. 173, pi. 47, figs. 2-4, 67; pi. 48, figs. 1, 2, 4, 1910 

3 Clark, U. S. G. S., Mon. LIV, p. 89, 1915. 

4 Cragin, Geol. Surv. Texas, 4th Ann. Kept., p. 155, 1893. 

Weno and Pawpaw Formations 109 

PI. 5, fig. 5; PI. 8, fig. 7 

1910: Epiaster aguilerae Bose, Inst. Geol. Mex., Bol. 25, p. 173, pi. 47, figs 2-4, 6-7; 

pi. 48, figs. 1, 2, 4. 
1920: Epiaster aguilerae Winton and Adkins, Univ. Texas Bull. 1931, p. 68. 


type I II 

mm. mm. mm. 

Length _ 77.2 66.2 48.0 

Width 69.1 65.5 43.5 

Height . 39.0 32.0 24.0 

Apical system to posterior margin 43.9 37.0 29.0 

Two individuals from the basal Fort Worth limestone near Fort Worth 
are referred to this species, which was described from Subdivision 5 (Fort 
Worth formation) of Cerro de Muleros on the basis of one imperfectly 
preserved individual. The individual figured in this paper is of the same 
proportions as Bose's individual but about one-seventh smaller. It differs 
also in having the antero-lateral ambulacra diverge at a greater angle, 
and in being slightly taller and longer from the apical system back : but 
the last two features mentioned are due in part to a small amount of end- 
wise crushing suffered by this fossil. In other respects it agrees with 
Bose's description. This echinoid is proportionately broader and shorter 
than the typical Fort Worth limestone, Hemiaster elegans Shumard, of the 
form figured by Adkins and Winton 1 and has a decidedly rounded, non- 
angular contour as compared with that species. It will be noted also that 
the ambulacra are narrower, more flexuous (near the ambitus), and sunk 
in much shallower grooves-than in H. elegans. The madreporite is smaller 
than in H. elegans- or in Macraster texanus Roemer. 3 No fascioles are 
visible. In longitudinal section H. elegans is much taller, straight-sided 
and less evenly rounded posteriorly than E. aguilerae, and its inter-ambul- 
acral areas, including the median posterior keel more elevated. In the 
individual at hand the periproct is situated lower than in material of 
H. elegans collected in the Fort Worth limestone at Fort Worth, but higher 
than in examples figured by Clark, 4 and the anterior notch is deeper than 
in Clark's figures but shallower than in some material collected by me. 

'Univ. Texas Bull. 1945, pi. 8, fig. 3. 

"Compare Clark, in Clark and Twitchell: U. S. G. S. Mon. LIV, pi. XL1II. 

3 B6se: Inst. Geol. Mex. Bol. 25, pi. XLVIII, figs. 1-3, 5. 

'Clark, ibid., pi. XLII, fig. 1-4. 

110 University of Texas Bulletin 

It is evident that the group of Hemiaster elegans of the Fort Worth lime- 
stone is in an unsatisfactory taxonomic condition and contains more than 
one species. 

The other individual of Epiaster aguilerae is smaller but similar in 
proportions to the one figured here. Like it also, the widest point is 
just anterior to the apical system and the contour is rounded; the form 
of the test is longer and somewhat more pointed posteriorly. The long- 
itudinal section is essentially the same. The periproct is situated higher 
and is perceptibly taller and less rounded, being pointed at both ends. 

HORIZON: Basal Fort Worth limestone. 

LOCALITY : Subdivision 5 of Cerro de Muleros ; Individual 1, one-half 
mile east of Texas Christian University, Fort Worth, Texas, locality 406. 

Individual 2, one-half mile southeast of Mt. Olivet Cemetery, Fort 
Worth, Texas, lower 10 feet of Fort Worth limestone. 

PI. 11, fig. 3 

MEASUREMENTS : Length, 89 mm. ; Width, 78 mm. ; Height, 52 mm. 

HORIZON : Top five feet of Weno formation, marl facies ; Pawpaw 
formation, marl facies. 

TYPE LOCALITY: 720, top of Weno limestone, one mile southeast 
of Riovista, Texas. 

DESCRIPTION : Test rotund, elevated, tapering posteriorly to a very 
narrow tall truncation sloping forwards at the bottom in the top of which 
the very small periproct is located. Contour same as E. wenoensis except 
more prolonged posteriorly; form straighter sided, much more elevated 
than that species, apical system proportionately farther forward. Base 
nearly flat, slightly raised on the posterior mid-line, but much less than in 
E. wenoensis, excavated for the peristome. Ambulacra straight, arranged 
as in E. wenoensis, inter-ambulacral areas notably more elevated. Un- 
paired ambulacrum with about 60 similar slit-like pore pairs obliquely set. 
Antero-laterals very long, with 90 or more pore pairs in each zone; all 
pores equal and similar ; postero-laterals with 80 or more pore pairs, equal 
similar slits. Peristome medium, transversely oval, 6.5x6.0 mm. ; periproct 
extremely small, circular, 3.5 mm. diameter, much smaller and situated 
relatively lower than in E. wenoensis. The description applies to the type 
individual. This species might be taken as an old individual of E. weno- 
ensis, but this is precluded by the differences cited above. The species 
having this characteristic size and form, is common in North Texas. 

Weno and Pawpaw Formations 111 


The genus Enallaster ranges from the Neocomian to the Turonian, but 
is especially abundant in the subtropical Cenomanian seas, where its great 
development and exuberance of closely related species constitute a special 
and complicated problem. The littoral deposits of the Mediterranean and 
the Texas regions contain a sequence of poorly defined Enallasters, in which 
the separate species are probably closely restricted in vertical range and on 
careful study will prove to have great stratigraphic value; the two areas 
mentioned have closely similar species. 

Enallaster differs from Holaster and Stenonia in having the ambulacra! 
pores sunk in ambulacral grooves instead of being flush with the surface ; 
it differs from Hemiaster and Epiaster in the exceptional depth of the 
anterior unpaired ambulacral groove and in the arrangement and length 
of the pore zones of the unpaired ambulacrum whose pore pairs are of 
alternate sizes instead of equal. Enallasters are of very diverse form, 
one group being flattened and short-ovoid, one group depressed but very 
elongate, and a third group rather tall and of elliptical contour. 

As defined by Cotteau, Enallaster contains only species in which the 
anterior unpaired ambulacrum contains alternate long and short pore 
pairs. Hemiaster differs from Enallaster in having the pore pairs of the 
unpaired ambulacrum slit-like and similar, and the pores of a pair sepa- 
rated by a rounded tubercle. The Texas species of Hemiaster are diverse 
and fall into two general groups. 

A. Postero-laterals very short, biconvex, apical system placed far back 
on test ; anterior row of antero-laterals with pairs of minute circular pores, 
form low, with long anterior slope. 

H. longisulcus (Adkins and Winton) 1 . 
H. riovistae Adkins. 

B. Postero-laterals long, more nearly straight, apical system nearly 
central ; anterior zone of antero-laterals with larger slit-like pores ; form 
more elevated and inflated. 

H. calvini Clark. 

H. elegans Shumard^ 

H. whitei Clark. 

H. sp. (Goodland limestone). 

H. comanchei Clark. 

Erroneously referred .to the genus Enallaster. 

112 University of Texas Bulletin 

PL 5, figs. 3 



Length 25.0 mm. 

Breadth 23.4 mm. 

Height 14.3 mm. 

Length from apical system to posterior border 9.0 mm. 

HORIZON : Upper five feet of Weno formation, marl facies. Base of 
Weno: base of Pawpaw clay. 

LOCALITY : 720 (type locality) , one mile southeast of Riovista, Texas, 
and one-half mile east of the Waco road ; 602, 618, near Fort Worth, Texas. 

DESCRIPTION TEST : Test oval in general outline, broadest point 
anterior to the center, less elongate and more abruptly truncated poster- 
iorly than H. riovistae n. sp. : anterior notch more pronounced than in 
that species and anterior groove shorter. Apical system located a little 
less than two-thirds the way back on the mid-line. The outline of the 
test seen from above is ovate, with angulations ; the anterior corners of the 
test are broadly round to the notch of the anterior sulcus, the posterior 
corners on the ambitus are abruptly rounded to the excavated periproct 
area. Oval surface inflated medially, the most prominent point being on 
the mid-line about two-thirds the way from the anterior end of the test. 
Aborally the highest point of the test is on the carina midway between the 
posterior ends of the short postero-lateral ambulacra and the test slopes 
gently anteriorly from this point, as in E. bravoensis Bose, and H. riovistae. 

Anterior unpaired ambulacrum sunk in the deep anterior sulcus which 
is relatively shorter and narrower than that of H. riovistae n. sp. 

Each zone has about 31 pairs of ambulacral pores. About the first 
twelve pore pairs are short, similar and equal except that they increase in 
size from the apical system anteriorly. They have each two equal short 
slits separated by a tubercle. Next come five pore pairs, three long and 
two short, alternating. Next come two groups of two short pairs each, 
alternating with long pairs. Thereafter anteriorly the pores are short and 
similar. Throughout this series in all the short pairs, the pores of a 
pair are separated by a tubercle, which in all the long pairs is lacking. 
The type agrees with this description. The narrow ambulacral plates, 
reaching the mid-line, have each two transverse rows of variable sized 
tubercles, irregularly arranged. 

Weno and Pawpaw Formations 113 

Anterolateral ambulacra: Diverge from apical system at angle of 180 
degrees, then turn forward, their middle parts making, if produced, an 
angle of about 45 degrees with each other ; then turn laterally and cross 
the ambitus at a point posterior to the anterior corner of the test. The 
anterior pore zone has 18 to 20 small, circular, closely spaced pore pairs. 
The posterior zone has about 27 pairs of slit-like pores, the anterior pore 
being much shorter. 

Posterolateral ambulacra: Short, inflated centrally diverge at angle of 
about 130 degrees from each other. Each zone has about 12 pore pairs, 
those of the posterior zone being more elongate than those of the anterior 
zone. In each zone the anterior pore is shorter than the posterior. 

Apical system: Four genital plates, their conspicuous thick-lipped per- 
forations making the four corners of a square. Oculars small, perforated. 

Peristome: Ovoid, depressed, posterior lip straight, with an elevated 
median carina behind it. 

Periproct: Ovoid, inferior margin extended downward; situated at top 
of vertically excavated area in posterior truncated area. 

This species is most similar to E. bravoensis Bose, from which it differs 
in many particulars. E. bravoensis in form resembles E. texanus (Roe- 
mer) and is the inflated texanus-like species which is widespread in the 
upper Washita and which has been so frequently mistaken for E. texanus. 
We have examples of it from the Weno to the Grayson formations, and it 
has been found in the Buda limestone (Whitney) . E. bravoensis is not so 
tall as E. texanus and is not therefore so inflated as. that species ; yet it 
is more rotund than E. wenoensis* and lacks the angular contour of this 
species. E. wenoensis is more ovate in form and does not have the long 
posterior narrowing of the test seen in many individuals of E. bravoensis. 
It is abruptly narrowed posteriorly and has a truncate posterior end. 
There is variation in the figured material of E. bravoensis in this regard, 
and in the absence of a designated type individual it is impossible to say 
which condition is typical for that species. Bose's plate XLI, figure 5, 
shows an individual in which the posterior narrowing is slight and the 
truncation is broad, as in E. texanus or E. mexicanus; in plate XLII, 
figure 9, the narrowing is prolonged and the truncation narrow, as in 
E. wenoensis. However, a constant and distinctive feature of E. weno- 
ensis is that the posterior end of the test is not merely truncate but is 
deeply excavated vertically, and in this excavation the periproct lies. In 
E. bravoensis as figured, the apical system is subcentral or at least far- 
ther forward than in E. wenoensis; the main limits of the antero-laterals 
therefore diverge at a wider angle (about 80 degrees) in E. bravoensis; 

114 University of Texas Bulletin 

and this position of the apical system is to some extent correlated with 
the elongation of the test. The anterior ambital notch in E. wenoensis 
is always sharper and deeper than in E. bravoensis; in the latter species 
it has the same form as in H. riovistae here described, while in this respect 
E. wenoensis and H. longisulcus (Adkins and Winton) are closely similar 
to each other. In E. wenoensis there is a conspicuous high point on the 
median .carina halfway between the apical system and the posterior end 
of the test; in E. bravoensis and H. riovistae the carina is low and the 
highest point is variable, often lying near the apical system. E. bravoensis 
in addition has a distinctly angular inferior inflation to the test which 
in our species is evenly rounded. 

PI. 8, fig. 4 

1910: Enallaster bravoensis Bose, Inst. Geol. Mex., Bol. 25, p. 168, pi. 41, figs. 5-10; 

pi. 42, figs. 2-12; pi. 43, figs. 1-2, 6-7. 

1916: Enallaster bravoensis Whitney, Bull. Amer. Pal. No. 26, p. 16, pi. 6, figs. 3-5. 
1920: Enallaster bravoensis Adkins and Winton, Univ. Texas Bull. 1945, p 58 pi 9 

fig. 11. 

This species is occasional in the Upper Washita formations, Weno to 
Buda, and in North Ttexas is still unknown from the lower formations. 
At Cerro de Muleros it is reported from subdivisions 5, 6, and 8 (Fort 
Worth to Grayson). This species differs from Enallaster wenoensis, which 
also is truncated and tapering posteriorly, by its more elevated and in- 
flated form, smaller depth of ambulacral grooves, and its taller and dif- 
ferently shaped longitudinal section in which the anterior slope is shorter, 
more abrupt and more rounded. 

ENALLASTER sp. aff. TEXANUS (Roemer) 

There are in the Upper Washita formations undefined species similar 
in form to Enallaster texanus (Roemer). These are abundant in the 
Weno and Grayson marls, and are in need of study and revision. 


PI. 5, figs. 1, 2, 4; PL 6, fig. 3; PI. 8, fig. 6 

This species may be recognized by its tall rounded form and its short, 
deep ambulacral grooves. It is somewhat variable in form and size, but 

Weno and Pawpaw Formations 115 

the most common variants are here figured. 

Form elevated ; outline angular, broadly truncated and shallowly ex- 
cavated posteriorly, with a shallow anterior ambital notch, widest just 
posterior to the antero-lateral ambulacra. The apical system is a little 
posterior to the center of the test, the distances in front of and behind it 
having the ratio 10:8. Ambulacra deeply excavated, the unpaired one 
being longest; the antero-laterals are longer than the postero-laterals (ra- 
tio 9:7) ; the antero-laterals diverge at an angle of about 105 degrees, the 
postero-laterals at about 45 degrees. The unpaired ambulacrum is slightly 
wider than the others. The posterior median keel and the interambulacral 
areas are elevated, the former being sharp-topped. Peripetalous fascicle 
visible but irregular. Pores of unpaired ambulacrum short, slit like, 
oblique, separated by a prominent tubercle. Pores of lateral ambulacra 
elongate transverse slits which are nearly equal in the forward and the 
rear zones. Peristome elongated transversely, with a prominent thick- 
ened posterior lip; periproct high, vertically elongate, ovate. The longi- 
tudinal section is distinctly elevated, posterior slope straight and inclined, 
anterior slope rounded, the highest point of the test being on the posterior 
median keel just back of the apical system. 

HORIZON: Weno to Buda formations. 

The Weno marl contains another species which has deeply excavated 
short ambulacra, much constricted at each end and flared in the middle. 
These ambulacra are remarkably short and inflated and have a very 
characteristic appearance. The whole ambulacral system is placed for- 
wards on the test, the posterior median keel and the interambulacral areas 
are elevated, she outline is almost circular and non-angular, the form 
is low, and the anterior median notch is shallow. 

This species has some resemblance to the poorly figured and described 
species Hemiaster bexari Clark. 

PI. 6, fig. 4; PI. 8, figs. 2-3,5 


Length on mid-line 25.5 

Width 23.5 

Height 14.0 

HORIZON: Top of Weno formation, marl facies. 

LOCALITY: 720 (type locality), one mile southeast of Riovista, 
Texas, and one-half mile east of the Waco road. 

116 University of Texas Bulletin 

DESCRIPTION Test: This species has nearly the form of Enallaster 
bravoensis Bose, but differs in many respects, notably in having the pore 
pairs of the unpaired ambulacrum all similar. Test low, elliptical in gen- 
eral outline, notched at the anterior ambitus, rounded laterally, with three 
distinct angulations, broadly truncate posteriorly. Anterior sulcus long, 
apical system situated slightly more than two-thirds the length of the 
mid-line from the notch of the anterior sulcus. Highest point of test on 
the low posterior median carina about one-fifth the length of the test from 
the posterior end. From this point the mid-line curves sharply poster- 
iorly to the top of the truncated posterior end. This point is only slightly 
taller than the edges of the anterior sulcus just in front of the apical 
system. Slope of test forward from apical system gentle, almost a 
straight line, similar to that of E. bravoensis Bose. The middle is the 
most inflated point on the test. Inferiorly the most prominent point is 
on the mid-line three-fourths the way back from the anterior end ; the shell 
therefore is tallest at this point and anteriorly is wedge-shaped, as in 
E. bravoensis Bose. There is an elevated median tuberculated area and 
the peristome lies in a deep depression of the recurved anterior sulcus and 
is bounded posteriorly by an overhanging pointed lip. Margins of shell 
sharply rounded on approaching ambitus, and coarsely tuberculate. 
Around each tubercle is a circlet of small tubercles, and the intervening 
spaces recovered by- fine granules irregularly scattered. Oval projections 
of postero-lateral ambulacra consisting of large smooth elongate plates 
with scattered tubercles and fine granules. Laterally the test bears sev- 
eral fascicle-like bands each consisting of three crowded rows of the 
smallest sized granules. 

Anterior unpaired ambulacrum: Long, shallow, sides nearly straight, 
making a rather shallow notch at the ambitus. Each pore zone has about 
32 pairs of transverse slit-like pores, the pores of a pair being separated 
by a conspicuously elevated, transversely elongate tubercle. The pores are 
similar and the ten nearest the apical system show a graduation in size; 
the others are approximately equal, except near the ambitus, where they 
are more nearly circular. The pore pairs lie each on an elongate ambul- 
acral plate which reaches the middle. Each plate has a double row of 
small granules. 

Antero-lateral Ambulacra: Diverge at an angle of 180 degrees and 
turn forward making over the central part of their course an angle of 
about 47 degrees with each other. They then diverge and cross the am- 
bitus far anteriorly. The anterior pore zone consists of about 22 pores 
of minute, closely spaced, circular pores, situated for the most part about 

Weno and Pawpaw Formations 1J7 

the diameter of a pore apart. These are situated in the antero-median 
quadrant of a quadrate or trapezoidal ambulacral plate which bears two 
or three large tubercles. The posterior zone consists of about 32 pairs, 
each having an anterior oval pore and a posterior wedge-shaped slit nar- 
rowest at the forward end. 

Postero-lateral ambulacra: Short, rather wide and bulging in the cen- 
ter, axes straight diverging at an angle of about 115 degrees from each 
other. The anterior zone has about 12 pairs of short slits; the posterior 
about 14 pairs of nearly equal longer slightly oblique slits. All of these 
pores decrease in size toward each end of the zones. 

Apical system: Four genital plates, the right anterior one being the 
elongated madreporite, the posterior pair slightly farther apart than the 
anterior pair ; four perforated oculars. 

Peristome: Transversely oval with a slightly emarginate lip. The lip 
posteriorly is elevated into a blunt high tip or carina. 

Periproct: In shape an oval, transversely situated but with the rounded 
inferior margin slightly bulged downward; each diameter (on the type) 
about 2.8 mm., situated high on posterior truncated surface two-thirds the 
way up. 

Aside from generic characters the following differences will assist in 
separating H. riovistae n. sp. from Enallaster wenoensis n. sp. E. weno- 
ensis has the apical system farther forward; the antero-laterals diverge 
at a slightly greater angle ; the anterior ambital notch is deeper and more 
sharply incised; the form is broader, less elongate, more nearly circular, 
distinctly less flat and more constricted posteriorly. The area in which 
the periproct lies is not merely truncate, but is sharply excavated giving 
a narrow vertical groove, while in H. riovistae the posterior end of the 
test is broadly truncate and the excavation is broad and shallow; and the 
pores of the anterior unpaired ambulacrum are in part alternating long 
and short pairs, instead of being all similar and separated by a tubercle 
as in H. riovistae. The more posterior position of the apical system of 
H. riovistae results in its having a longer anterior sulcus, it being inter- 
mediate in this respect between E. wenoensis and H. longisulcus. The an- 
tero-laterals are in many individuals which are here referred to E. weno- 
ensis much more sunken than in H. riovistae. The only other described 
species with which H. riovistae might be confused is E. bravoensis which 
has long and short pore pairs in the anterior unpaired ambulacrum instead 
of having all the pore pairs similar. H. longisulcus (Adkins and Winton) 
has these pore pairs similar, but it is at once distinguished by its lower, 
more elongate form, and by the unusually long anterior sulcus and the con- 
sequent posterior position of the apical system. 

118 University of Texas Bulletin 



PI. 10, figs. 12-16, 19-20 


Length 17.0 mm. 

Height 13.4 mm. 

Thickness 8.3 mm. 

HORIZON : Blue shale and red clay-ironstones of upper half of Weno 
formation, Red River region. 

LOCALITY : 601, pit of brickyards, one and three-fourths miles south- 
east of Gainesville, Texas (type locality) ; 604, cut of Frisco track, three- 
fourths mile north of Union Station, Denison, Texas. 

DESCRIPTION : Shell inequilateral, sub-equivalved, 'sub-triangular in 
contour, with fine radial ribs. 

Right valve, exterior: Beak sharply rounded, angle 100 degrees; a 
straight rounded ridge runs from the umbo to the anterior angle, making 
with the anterior margin a long low triangle* whose other two sides are 
almost straight portions of the anterior margin. These portions are in 
length as two to one, the dorsalmost portion being the lunger, and make 
with each other an angle of 15 degrees. The ventralward portion, if ex- 
tended, would make with the extended ventral side an anterior angle of 
60 degrees; the actual angle is sharply rounded. The ventral margin is 
gently convex downward, and extends backward to the sharply rounded 
posterior angle (90 degrees). The postero-dorsal margin is straight. 

The ornamentation consists of about 47 very flat low radial ribs which 
are unbranched and continuous from beak to ventral margin. Between 
these lie fine straight depressions one-sixth to one-eighth the width of a 
rib. The ribs are crossed by fine scalloped growth lines with the convex- 
ities pointed ventrally, giving to the growth lines a fine crenulate appear- 
ance. On the anterior area (lunule) the ribs disappear and the growth 
lines thicken slightly. This area contains a radial anterior ridge and a 
concurrent posterior depression ; the growth lines in crossing these are 
crenulate. TWO deeper concentric constrictions representing stages of 
growth lie in the ventral half of the valve. 

On the shorter posterior area (escutcheon) the growth lines turn dor- 
sally and passing over a radial depression and a radial ridge, converge to 
the margin. 

Right valve, interior: The rounded, posteriorly directed beak is slightly 
elevated over the posterior margin. This margin is gently convex over 

Weno and Pawpaw Formations 119 

its dorsal three-fifths and bears a taxodont series of nine teeth of which 
the two dorsalmost and the one ventralmost are shorter and narrower 
than the others. The antero-ventral two-fifths of the margin is concave 
and lies just posterior to the truncately elliptical scar of the post-adductor 
muscle. The posterior end of this margin is the posterior angle, from 
which the rounded ventral margin runs to the anterior angle. This margin 
is more sharply rounded near the posterior angle. The antero-dorsal mar- 
gin is distinctly bulged, and its dorsal two-thirds bears a taxodont series 
of twenty teeth, which taper in size at each end. 

Beneath the umbo is a narrow triangular pit directed downward and 
anteriorly; and posterior to it is a parallel tooth containing along its 
length, except at the top, a sulcate depression. 

Left valve, exterior: The beak is rounded and forms an angle of about 
105 degrees. The posterior area is contained between the straight post- 
erior margin and a curved ridge which is the arc of a circle. In this area 
the growth lines turn sharply dorsally and converge at the margin. In 
its center is a radial elevation on whose outer surface are irregular crenu- 
lations which are oblique to the growth lines and continuous with those on 
the main portion of the valve. Lateral to the elevation is a concurrent 
depression and dorsal to it a small plane area. The posterior angle is 
100 degrees. The ventral margin is curved ; and more sharply so at the 
posterior end. The anterior area is a triangular space included between 
the convex anterior margin and a concurrent but divergent ridge which 
runs from the beak to the anterior angle. It bears numerous^ coarse 
crenulations which are continuous with those over the main body of the 

The ornamentation of the valve consists of numerous radial simple flat 
ribs similar to those of the right valve; and concentric depressions and 
growth lines. The two valves fit together evenly with a slight ventral 

Left valve, interior: This valve is essentially similar to the right valve. 
Anterior to the beak and ventro-lateral to the taxodont series of teeth 
is an elongate tooth pointed antero-ventrally and fitting into a socket in 
the right valve. Its end lies below the tenth tooth anterior to the beak. 

Type individual: This description is compiled from three individual? 
of which the first, showing the exterior of the right and left valves, is 
to be considered the type individual. It and the other two, as many of 
the other individuals, were found in the blue marl of the upper half of 
the Weno formation, 20 feet below Quarry limestone in cut of Frisco track, 
one mile north of Union Station, Denison, Texas (604). 

120 University of Texas Bulletin 

PI. 10, figs. 10-11 


Breadth 8.5 10.2 13.0 

Height 14.9 17.5 18.5 

Length 20.5 23.7 26.0 

HORIZON : Weno formation, blue shale, Red River region, occasional ; 
clay ironstone, occasional. 

LOCALITY: 604, Frisco cut, three-fourths mile north of Union Sta- 
tion, Denison, Texas (type locality) ; 601, pit of brickyard, one and three- 
fourth miles southeast of Gainesville, Texas. 

DESCRIPTION: Shell sub-equivalved, moderately inflated, inequi- 
lateral, beaks placed back of the middle of the valve. Ventral margin a 
long, sub-elliptical curve, sharply angulated posteriorly, more rounded an- 
teriorly. Anterior margin long, slightly convexed, beaks opposite, approx- 
imate; posterior margin shorter than anterior, nearly straight, lacking 
a prominent incision just posterior to the beaks. Anterior areas cres- 
centic, together forming an elongate biconvex strip, posterior areas form- 
ing a strip proportionately shorter but equally wide. These are crossed 
by plain recurved growth lines. 

Valves nearly smooth in appearance; ornamentation consists of numer- 
ous fine. simple radial s^riaeiform ridges, crossed by growth lines and 
growth rings. These ridges on reaching the ventral border form a slightly 
incised, non-crenulate edge. Hinge taxodont, essentially as in Nucula 

This species differs from N. hokonis in its form and ornamentation. 
The anterior margin 'is straighter and longer; the posterior margin is 
straighter and lacks the sharp notch just back of the beaks, having in- 
stead a gentle curvature ; the posterior "areas" are much more pronounced 
in side view, and instead of lying flat are elevated at the line of junction 
of the valves by a posterior projecting carina. The ornamentation at once 
distinguishes the two species, for in N. nokonis the radial ribs are very- 
pronounced and the concentric growth lines on crossing them form a 
system of prominent squares ; the concentric ribs on approaching the an- 
terior border become zigzag or wavy making a conspicuous V-shaped an- 
gulation, and in the same region the concentric ribs become crenulate and 
lamellated. The radial ribs form a prominent scalloped edge at the ven- 
tral margin of the valve. 

Weno aud Pawpaw Formations 121 

PI. 10, fig. 6 


Length 9.2 12.6 8.1 6.7 8.0 

Height 7.0 9.5 5.0 '4.9 6.2 

Thickness 6.6 9.5 5.6 4.6 6.4 

< Length of -hinge line 7.3 9.9 6.8 5.7 7.0 

HORIZON: Pawpaw formation, clay faciea, widely distributed, John- 
son to Denton counties ; ironstone and sandstone f acies, widely distributed, 
Denton County to east of Bennington, Oklahoma. A similar, and prob- 
ably identical species of Area occurs in the Grayson marl and clay at 
Burleson and Roanoke, Texas; in the Denton clay at Denison, Texas; and 
in the Duck Creek marl, Grayson to Johnson counties, Texas. 

LOCALITIES: 714, near Fort Worth, Texas (type locality), all Paw- 
paw localities in the Fort Worth region. This fossil is found wherever 
Pawpaw fossils occur, in Denton, Tarrant and Johnson counties, and 
practically so in the Red River region. Its zone of abundance is one of 
the most reliable markers of the Pawpaw formation. 

DESCRIPTION: Shell small, valves very inflated, subequal inequi- 
lateral, taller posteriorly than anteriorly. Beaks prominent, remote, pro- 
jecting, rounded, situated slightly anterior to the center of the shell. An- 
tero-dorsal margin short, concaved; posterior margin longer and nearly 
straight. Anterior margin short, sharply rounded, ventral margin long 
and nearly elliptical, dorsal margin broadly rounded. Hinge line long 
and straight and marked by a crenulated thin ridge in casts of the in- 
terior. The shell gapes slightly at its posterior end. The valves are orna- 
mented by numerous low, fine, subequal radiating striae, which equal in 
width the valleys between them ; and a few (7 or more) unequal, coarse 
concentric ridges lying mainly on the ventral half of the valve. 

This Area may be distinguished from others described from the Texas 
Comanchean strata by its form and size. It is a very characteristic pyrite 
and hematite fossil and is widespread geographically in the Pawpaw form- 
ation, and in addition appears to have considerable vertical range, reap- 
pearing in the Upper Washita in association with pyritic Engonoceras, 
Turrilites, Hamites, Scaphites and starfishes with each invasion of the 
clay and ironstone phase of deposition. 

122 University of Texas Bulletin 


1888: Dalliconcha invaginata White, Proc. Acad, Nat. Sci., Phila., p. 35, pi. 2, figs. 4-5. 

1889: Gervilliopsis invaginata Hill: Geol. Surv. Texas Bull. 4, p. 9. 

1896: Gervilliopsis invaginata Stanton and Vaughan, Am. Journ. Sci., IV series, vol. 1, 

vol. 1, pp. 21-26. 

1910 : GervUleia invaginata Bose, Inst. Geol. Mex., Bol. 25, p. 87. 

1920: Gervilliopsis invaginata Adkins and Winton, Univ. Texas Bull. 1945, p. 67, pi. 18, 
fig. 1. 

This shell abounds in the lower Weno of Cooke County, where on fresh 
exposures it is found with the nacreous shell intact. It has a restricted 
vertical range and is a reliable marker for the basal Weno north of the 
Brazos River. It has not been reported from South Central Texas. 

Stanton and Vaughan, however, record the species from subdivision 6 
(Weno-Pawpaw) of Cerro de Muleros. 


The known distribution of carmata-like species in Texas has already 
been published. 1 Pervinquiere- has figured types of Ostrea carinata Lam- 
arck ; and Texas material is now being assembled for a critical study and 
comparison with related European material. Oysters of the group of 
0. carinata and widespread in North, Central and West Texas at different 
stratigraphic levels, and among them a zone of abundance of the smaller 
forms in the upper part of the Weno limestone (Quarry group of North 
Texas) and a scattering representation in the Pawpaw formation. 

OSTREA sp. aff. DILUVIANA Linnaeus 

There are in the Weno and Pawpaw formations three oysters with zig- 
zag coarse margins and ribbed valves, resembling the group of Ostrea 
diluviana. One of these occurs in the Weno and Mainstreet limestones 
and is similar to that figured by Hill from the Austin Chalk (U. S. G. S.. 
21st Ann. Kept., pt. 7, pi. XLV, fig. 2). Another species from the Weno 
marl is smaller and thinner, and the margins are crenulate (Univ. Texas 
Bull. 1945, pi. 16, fig. 1). A third unfigured species from the Weno marl 
has few prominent zigzag ribs of varying height. These species will likely 
be found to have considerable vertical range. 

1 Winton and Adkins, Univ, Texas Bull. 1931, p. 57; Adkins and Winton, Univ. Texas 

Bull. 1945, p. 59. 
2 Pervinquiere, Pal. Univ., 3 me ser., 1910, fiches 197-198. 

Weno and Pawpaw Formations 123 


1860: Ostrea quadriplicata Shumard, Trans. St. Louis Acad. Sci., vol. 1, p. 608. 
1879: Ostrea quadriplicata White, llth Ann. Kept. U. S. G. and G. Surv., Terr., pp. 275- 

276, pi. 5, fig. 6a. 
1920: Ostrea quadriplicata Adkins and Winton, Univ. Texas Bull. 1945, p. 60, pi. 16, 

figs. 6-10. 

This species has not been seen above the Mainstreet limestone, where 
it is rare, or below the Denton marl. It is abundant at the top of the 
Denton marl, with Ostrea carinata and Gryphea washitaensis ; and at the 
Weno-Pawpaw contact in the Quarry limestone, with Ostrea carinata. 
Gryphea washitaensis and cidarid spines. 

This species is not known in South Central Texas, but is abundant near 
El Paso in subdivision 6 (equivalent of Weno-Pawpaw). 

EXOGYRA sp. off. ARIETINA Roemer 

A small species of Exogyra, juvenile and young adult stages, was found 
in the basal Weno at locality 611, near Fort Worth, Texas. The evolution 
of the arietina group leaves large gaps to be filled in ; the group is known 
from the Goodland limestone, upper third, and the Kiamitia marl (E. spp. 
aff. plexa, ribbed and non-ribbed), from the Duck Creek limestone (E. 
plexa) ; the Mainstreet limestone (E. arietina) and the Grayson marl (two 
species aff. E. arietina). 


PI. 11, fig. 4 
1895: Pecten inconspicuus Cragin, Colo. Coll. Stud. 5, 1894 (1895), p. 61. 

Cragin's description follows: 

"Shell small, thin, subcircular, a trifle higher than long, slightly trun- 
cated anteriorly and posteriorly, right valve gently convex, its outer sur- 
face smooth except for faint concentric striae and a few remote, subim- 
bricate growth-lines; umbonal angle sharp at apex, nearly a right angle; 
anterior ear (imperfect in the type) re-entrant below, as indicated by the 
direction of the striae upon it, outline of posterior ear marking an obtuse 
angle, its posterior margin rather more than one and a half times as long 
as its dorsal. Left valve unknown. 

"MEASUREMENTS : Height 9.5, length 8.75, convexity of left valve 
1 mm. 

124 University of Texas Bulletin 

"OCCURRENCE : On slope of Pawpaw Creek,'east of Denison, Texas, 
in red ochraceous shell-conglomerate of the Pawpaw clays. The associate 
fossils are Ostrea quadriplicata, Tapes dentonensis, Yoldia microdonta 
Turritella seriatim-granulata, Sphenodiscus, Turrilites, etc." 

Although Cragin's description is very brief and general, it fits a common 
Weno species of Pecten in many respects; the locality also makes it prob- 
able that our Gainesville and Denison material is to be referred to Cragin's 
species. 1 

HORIZON: Ironstone and shale facies, upper two-thirds of the Weno 
formation. Basal Pawpaw formation, sand-ironstone facies. Very rare 
south of the Red River region. 

"LOCALITY: Cut of St. Louis and San Francisco Railway, one mile 
north of Denison, Texas (PI. 11, fig. 1) and pit of brickyards, one and 
three-fourths miles east of Gainesville, Texas. Numerous localities in 
Cooke and Grayson counties, Texas. In the pit of the Gainesville brick- 
yard there are extensive sheets of nacreous shells consisting largely of 
Pecten inconspicuus, Gervilliopsis invaginata and prodissoconchs and later 
embryonic stages of Gryphea washitaensis. 

DESCRIPTION : Shell slightly elevated, smooth, jnequivalve, inequi- 
lateral ; ventral margin almost the. arc of a circle whose diameter is the 
antero-posterior dimension of the shell. Antero-dorsal margin almost 
straight, postero-dorsal margin slightly concave near middle and more 
elevated by a sharp fold above the ear than the antero-dorsal margin 
the two make an angle of about 95 degrees at the umbo, the angle being 
pointed and very slightly rounded at the tip ; the angle made by lines drawn 
from the extremities of the two margins to the umbo is about a right 
angle. The umbo projects slightly over the hinge line. Anterior and 
posterior ears triangular, the latter having a longer base along the margin 
than the former, and having nearly twice the area. Hinge line straight, 
making an angle of about 46 degrees with the antero-dorsal margin and 
an angle of about 42 degrees with the postero-dorsal margin. The term- 
inal angle of the anterior ear is about 95 degrees; of the posterior ear, 
about 100 degrees. The latter angle is broadly rounded. 

The ears have fine parallel sigmoid growth line which bend toward the 
umbo at the hinge line, but at the dorsal margin bend anteriorly and 
posteriorly and after ascending these margins, course concentrically across 

'This species has never been figured, so far as I can discover; the type is presumably 
in the Colorado College museum, but efforts to get information about it have been 

Weno and Pawpaw Formations 125 

the valve. The growth lines on the valve are fine but unequal; there are 
also irregular coarser, more widely spaced imbricated rings. 

In addition, the right valve and its ears are ornamented with numerous 
fine striaeiform radial curved elevated costellae which spread fan-wise 
as they approach the margin; these are irregularly truncated near the 
ventral margin, and on the ears, by intersection with the coarser radial 
striae, form a network of small squares. 

The left valve is apparently slightly concave and has a similar structure 
to the right valve. 


1919: Neithea georgetownensis Kniker, Comanchean and Cretaceous Penctinidae of 

Texas. Univ. Texas Bull. 1817, p. 31, pi. VI, figs. 1-3. 
1920: Pecten georgetownensis Winton and Adkins, Geology of Tarrant County, Univ, 

Texas Bull. 1931, pp. 22, 64, 66. 
1920 : Pecten georgetownensis Adkins and Winton, Univ. Texas Bull. 1945, p. 70, pi. 12, 

figs. 5-6. 

This species may be distinguished by its form and by the radial grooves 
located on the center of the primary and secondary ribs of the right or 
both valves. These grooves, however, occur sporadically on other species 
of Pecten of the P. subalpinus type. It marks the basal third of the Weno 
formation, marl facies, and is associated with Turritella worthensis, 
Ancycloceras bendirei, Remondia acuminata Cragin, Pedinopsis symmetrica 
Cragin, and numerous widely ranging species. It is widespread and abund- 


PI. 6, fig. 2 

MEASUREMENTS (type individual) : 

Antero-posterior 23 mm. 

Dorso-ventral . 23 mm. 

Right-left 18 mm. 

HORIZON AND LOCALITY: Basal Weno formation, marl facies, 
locality 618, near Fort Worth, Texas (type locality) ; middle Weno shales, 
"buff marl," below the main GerviUiopsis invaginata zone, locality 601, 
near Gainesville, Texas. 

DESCRIPTION : This Venericardia somewhat resembles V. alticostata 
Conrad var.: of the Eocene, but has the ribs more strongly imbricated 

126 University of Texas Bulletin 

and the ventral margin less nearly circular. 1 I know of no other similar 
species from the Comanchean. 

Shell oblique, elliptical in outline except for the projecting, elevated 
umbonal region. Beaks greatly recurved. Ventral margin almost an el- 
lipse, sharply curved below the beak, gently curved behind ; dorsal-posterior 
margin nearly straight. The valves have about 24 sharply raised ribs, 
which bear remote but unevenly spaced, elevated, nodose imbrications. 
The lateral dimension of the shell is thick, and the species varies some- 
what in outline. The hinge and other interior details are unknown. 

PI. 10, figs. 21-26, 32 

This beautiful Protocardia occurs as casts and molds in the clay-iron- 
stone of the Gainesville brickyards and shows in nacreous preservation 
the minutest details of the exterior and the interior of the shell. Most 
frequently the shell has crumbled into a friable powder and falls to pieces 
as the rock is broken open. It then leaves in the ironstone excellent molds 
of the exterior of the shells showing the radial and concentric striations 
of the exterior and the details of the hinge, and casts of the interior 
showing details of the dentition, the two muscle scars, pallial line, etc. 
Frequently the shell has been removed by weathering and the ironstone 
carries a > cavity of its exact shape bounded by the cast and the mold. 
Rarely in the ironstone but usually in the blue shale, the original shell 
is preserved intact. 

The Protocardia group of the Texas Comanchean has not been satis- 
factorily studied and its species are still poorly defined. As in many 
other Texas genera this uncertainty can be resolved only by a critical 
description and photographic illustration of the types. Here as in other 
genera where new species might have been founded, this has not been 
done pending a better understanding of the relations of the species already 

Shell inequivalve, inequilateral, biconvex, ornamented with sixteen or 
more serrate radial lines and about 75 round topped subequal concentric 
ribs separated by narrow valleys. The dorsal margin of the shell is 
arcuate interiorly, and anteriorly is more thickened. It bears several im- 
bricated lamellae parallel to and below the hinge line. The region under 
the beak is deeply excavated. 

'Harris, The Midway Stage, Bull. Amer. Pal., 4, pi. 4, flg. 12. 1896; and, The Lignitic 
Stage, Bull. Amer. Pal., 9, pi. 11, fig. 1, 1897. 

Weno and Pawpaw Formations 127 

HORIZON : Middle and Upper Weno shale and clay-ironstone. 

Locality of figured material : 604, cut of St. Louis and San Francisco 
track,- three-fourths mile north of the Union Station, Denison, Texas ; the 
species occurs throughout the Red River region, and is abundant at locality 
601, pit of brickyards, near Gainesville, Texas. 


PI. 10, figs. 1-4 


Length 10.6 11.6 11.2 

Breadth (one valve) __. 3.8 4.4 4.0 

Height 7.7 8.1 8.0 

Length of rostrum 2.0 2.5 2.5 

HORIZON: Weno formation, upper half, clay and ironstone phase, 
abundant; Pawpaw clay, rare. Abundant in the Red River region. 

LOCALITIES: 604, near Denison, Texas (type locality); 601, near 
Gainesville, Texas. 

Shell small, inequivalve, concentrically ribbed with a truncated rostrum. 

Right valve, exterior: Form a very irregular quadrilateral ; size small. 
Viewed directly from above, the valve is roughly pear shaped and consists of 
a very inflated rotund body and a narrowed and depressed posterior siphon 
tube or rostrum. The umbonal margin is roughly the arc of a circle whose 
diameter equals the height of the shell. This border passes by a sharp- 
pointed curve of 120 degrees into the anterior border, which is almost a 
straight line making an angle of about 45 degrees with the dorso-ventral 
axis of the valve. The anterior border passes into the ventral border by a 
sharply rounded curve which is approximately the arc of a circle one-half 
the diameter of the dorso-ventral dimension (height) of the shell ; the anter- 
ior and ventral borders if extended would meet at an angle of about 55 de- 
grees. The ventral border is very slightly convex and this approximates 
a straight line through one-half the greatest length of the shell, where it 
is perpendicular to the dorso-ventral axis. A little anterior to its middle 
there is slight concavity which involves the lower two or three ribs of 
the shell. The ventral border now curves upward and posteriorly, reach- 
ing the narrowed siphon tube. 

The snout-shaped siphon tube lies opposite the middle one-third of the 
height of the shell and is roughly a right angled isosceles triangle whose 
hypotenuse is the line of attachment to the body of the valve. This line 
of attachment is a narrow constricted or depressed zone which notches 

128 University of Texas Bulletin 

both the ventral and the dorsal margins of the valve and gives to the 
rostrum an inflated appearance; the notch in the dorsal margin is the 
deeper and more pronounced one. Posterior to the depressed zone and 
running slightly divergent to it is a rounded ridge which assumes a con- 
ical inflation as it approaches the postero-ventral extremity of the ros- 
trum; on the rostrum dorsal to this ridge is a parallel narrow depression 
and beyond it a rounded inflation which forms the postero-dorsal extrem- 
ity of the rostrum. 

The ornamentation consists of thickened, rounded, concentric ribbings, 
which are broadly flattened on their tops and descend by almost right- 
angled sides to small plane-bottomed valleys lying between them. On the 
dorso-ventral axis the widths of ribbings and valleys are about as 2 to 1. 
The ribs and valleys decrease in width at the anterior margin and at the 
constriction of the siphonal tube. 

The ventral one-half of the shell contains 12 rounded ribbings ; the dorsal 
one-half contains 17 rounded ribbings of similar form but of constantly 
decreasing size, and in addition in the umbonal region 25-30 fainter rib- 
bings which resemble growth lines. 

These 29 heavier ribbings course posteriorly making broad downward 
convexities to the region of the siphon tube constriction ; their posterior 
ends lie in the depressed zone mentioned. They then rise onto the elevated 
ridge which lies near the anterior end of the rostrum, and course over the 
inflated rostrum to its dorsal margin. On this elevated ridge the com- 
ponent growth lines in the ribbings apppear as slight thin imbricated 
lamellae. Not all of the ribbings run continuously from the anterior to 
the posterior margin. Towards the anterior margin some of the rib- 
bings, especially the dorsal ones fuse by twos into broader and more de- 
pressed flat bands. The ribbings on a whole are more flattened and more 
consolidated on the anterior margin, and more resolved into growth lines 
on the posterior margin, in the neighborhood of the siphon-tube. In one 
ribbing, splitting is seen over the middle half of the shell. In one place a 
small auxiliary ribbing between two of usual size, is seen over the middle 
half of the shell. 

The right valve is. somewhat larger than the opening into which the 
left valve fits, so that the arched, rotund margins of the right valve enclose 
an elliptical basin shaped visceral space upon which the reduced left valve 

Right valve, interior: Viewed directly from above, the cavity of this 
valve has an elliptical contour except at the siphonal end where the mar- 
gins of the ellipse are drawn out so that each margin has an inward facing 
convexity ; the dorsal margin then slants ventrally and posteriorly to meet 

Weno and Pawpaw Formations 129 

the ventral margin. There is also a deep rounded concealed recess under 
the umbo, from this viewpoint. The anterior adducter muscle scar is a 
small subcircular basin-like depression with a raised rim whose dorsal 
border connects with the pallial line, a faint narrow groove which ap- 
proaches the ventral margin as it courses towards the post adducter scar. 
This scar occupies a rounded-triangular elevated area lying between two 
more elevated ridges. 

The more anterior ridge is a shelf-like lamina which separates the body 
cavity proper from the siphonal (rostral) extension of the shell; and as 
it passes umbonally it unites with the more posterior ridge forming a 
U-shaped junction and enclosing between the two ridges the scar of the 
adductor muscle. The united ridge continues anteriorly as the ventral 
edge of a broad excavated pit or socket. The external (prismatic) layer 
of the valve forms a distinct umbonal imbrication which makes up the 
dorsal edge of this socket. This inner edge of the external layer passes 
anteriorly, including the umbo but excluding the tooth against which it is 
apposed; and proceeds to encircle and parallel the anterior and ventral 
margins of the valve as far as the ventral border of the rostrum, making 
an imbricated impression about midway between the pallial line and the 
ventral margin. The thick external portion is cancellated and penetrated 
by irregular concentric airspaces formed by the loose apposition of long 
lamellae. The external prismatic portion makes up .8 of the thickness 
of the shell ; the inner portion is porcellanous and in places pearly-irides- 

Rostrum: The inner layer emerges from the body cavity proper onto 
the rostrum, where it is thrown into two small elevated folds which cross 
each other almost at right angles and consequently form four depressed 
spaces sloping away from them at either side. The shorter fold is in 
the antero-posterior axes, and the longer one is continuous with the um- 
bonal imbrication mentioned above. 

DISCUSSION : The description of the unfigured Cragin species C. cras- 
sicostata, agrees with this species in some particulars, but disagrees es- 
pecially in the number of concentric ribs. In Cragin's Kansas material 
this number is "7 or 8 on the basal half of a shell the same number of 
millimeters high," while in our material the number is 11 to 12. Cragin 
states that the Kansas and the Denison specimens show "no differences of 
specific value," but further information of a deciding nature is not forth- 

Cragin's description of the species, Corbula crassicostata, is as follows: 1 

Cragin, Colo. Coll. Stud., 5, 1895, p. 61. 

130 University of Texas Bulletin 

"Corbula crassicostata, sp. nov. 

"Shell triangular-ovate, gibbous ; nearly as broad as high, shorts ; gaping 
posteriorly by a short, conically inflated, gently truncated rostrum, which 
is placed high above the base of the shell ; unbones placed in advance of 
the middle, that of the right valve only moderately high arched, its sum- 
mit obtuse ; surface ornamented with very coarse, flattish-topped, concen- 
tric ribs, separated by abrupt, deep narrow intervals. There are seven 
or eight of the ribs on the basal half of a right valve the same number 
of millimeters high. 

"Measurements : Height 7.5, length 10, breadth about 7 mm. 

"Occurrence: In arenaceous limestone bands of the Kiowa shales at 
Belvidere, Kansas ; in Nos. 2-4 of the writer's 'Belvidere Section.' 

"So far as the writer can judge from material now in hand, the similar 
Corbula that abounds in the condition of casts and molds in Texas, presents 
no differences of specific value from the Kansas shell above described. The 
casts show that the pallial line is very sharply impressed." 


PI. 9, figs. 7-24; PI. 10, figs. 7-9 

Length 17.4 mm. 

Height 12.1 mm. 

Breadth 7.7 mm. 

Difference in length of valves 2.4 mm. 

HORIZON : Blue shale and clay-ironstone layers of upper half of Weno 
formation, Red River region, abundant; Pawpaw clay, occasional. 

LOCALITIES: 604, cut of Frisco track, three-fourths mile north of 
Union station, Denison, Texas (type locality) ; 601, pit of brickyards one 
and three-fourths miles southeast of Gainesville, Texas; numerous other 
localities in Cooke and Grayson counties, Texas. Rare, as limonite stained 
casts in the Fort Worth region. 

DESCRIPTION : Shell small, inequivalve, almost smooth, with a short 
pointed rostrum. 

Right valve, exterior: Valve rather inflated, evenly rounded, its out- 
line almost a truncated ellipse. As seen from directly above, the umbonal 
angle is about 120 degrees ; the dorso-anterior margin is thereafter almost 
straight for about one-third the greatest length of shell ; the anterior mar- 
gin then describes an evenly rounded curve, a portion of an ellipse, which 
continues to the middle of the ventral margin ; here the margin is more 
nearly straight, but again curves more sharply dorsally and posteriorly, 
and reaches the posterior (rostral) angle. This angle is 90 degrees and 
is very slightly rounded-acuminate. The postero-dorsal margin is almost 

Weno and Pawpaw Formations 181 

straight, having a roughened, striate protruding area the rostrum reach- 
ing to the umbo; and anterior to it is the straight posterior margin of 
the valve. 

The greatest height of the valve is near its center. Its convexity is 
greater on the umbonal margin than on the ventral margin; from the 
center the surface slopes gently to a line, marked in places by a prominent 
growth line, below which the surface is curved at a sharply rounded angle 
of 90 degrees to the margins of the valve, giving to the valve a charac- 
teristic geniculated and basin-like appearance. The rim of the valve 
thus slopes inward at all points except on the dorsal margin of the ros- 
trum, so that the margin of the valve has a smaller circumference than 
the prominent growth line mentioned above. 

The ornamentation consists of radial striae and concentric growth lines. 
The radial striae are fine, unbranched, wavy, or punctate lines which end 
near the geniculation. The concentric growth lines are more conspicuous 
(toward the ventral margin they resemble fine ribs), and pass posteriorly, 
turning sharply dorsally at the line of junction of the main body of the 
valve and the slightly developed rostrum. They then pass dorsally in 
straight lines which give to the elongate triangular rostrum a roughened 
striated appearance. 

Right valve, interior: As viewed directly from above the interior of 
the right valve has three prominent contours : the outer one is the margin 
of the valve ; the middle one is a narrow groove, the junction between the 
thicker outer (prismatic) shell layer and the thinner inner (porcellanous) 
shell layer; the innermost contour is the limit of the main body cavity. 
The first two are the shape of a long ellipse, and are situated a short 
distance apart ; they begin at the antero-dorsal one-third of the prominent 
tooth, and run concentrically around the anterior and ventral margins of 
the valve, making an evenly rounded elliptical curve to the postero-ventral 
extremity of the rostrum. The innermost contour encloses roughly a sub- 
quadrate area whose boundary begins at the ventral margin of the tooth 
and describes a slight curve to the dorsal end of the anterior adductor 
scar. Here it runs almost straight ventrally with a slight posteriorward 
convexity formed by the scar, in such a manner that a sharp-edged, cres- 
cent shaped shelf, elevated above the main body cavity, is formed between 
it and the middle contour mentioned. The scar is pear-shaped and its 
inflated ventral end lies at the widest point of the shelf. The shelf con- 
tinues along the interior of the ventral side of the visceral space to a point 
one-third the way from the anterior end, and then fuses with the wall of 
the valve. Just anterior to it lies the pallial line, a narrow groove with 
a slight and irregular interior elevated crest which descends to the bottom 

132 University of Texas Bulletin 

of the visceral space and proceeds backward to a point underneath the 
posterior adductor muscle scar. Here it turns backward making a 45 
degree angle, then turns straight dorsally, making with its former course 
a 90 degree angle, and reaches the lower angle of the scar. This rounded 
triangular scar likewise lies on an elevation formed by the inner contour 
mentioned, which passes dorsally and anteriorly, then turns anteriorly 
reaching the ventral border of the tooth. It thus leaves dorsal to it and 
posterior to the tooth, a kidney-shaped pit, into whose posterior border a 
small tooth projects. 

Left valve, exterior: This valve is smaller and distinctly shorter than 
the right valve, but has almost the same depth. Its smaller length is due 
to the shortness of the rostrum which fails to cover about one-half the 
rostral area of the right valve, and thus leave a narrow wedge-shaped gap 
for the siphon tubes. The left valve is in contour an obliquely truncated 
ellipse. Seen from above, it has an umbonal angle of about 100 degrees 
and an almost straight antero-dorsal margin. This continues as a sharply 
and evenly rounded curve into the ventral margin which is gently curved, 
but which posteriorly curves more sharply, reaching the tip of the ros- 
trum. The postero-dorsal margin is roughly a straight line, except for a 
slight bulging near the posterior half. The valve has a marginal gen- 
iculation of about two-thirds the height of the corresponding one on the 
right valve, and consequently a basin-like form for the entire valve. 

The ornamentations consist of growth lines and weak concentric ribs, 
of which there are about seven below the geniculation, and 26 or more 
above it, the ribs decreasing in size in the dorsal one-third of the shell. 

The ventral one-half of the valve, above the geniculation, bears about 
12 ribs. 

Left valve, interior: This valve has a truncate elliptical margin. It 
may be divided into two regions : the visceral cavity and the rostrum. The 
anterior part lacks the prominent shelf seen in the other valve. The 
visceral cavity is a subquadrate depressed area from which a shallow 
curved recess extends under the beak. Its margin is separated from the 
posterior margin of the valve by the triangular shaped rostrum whose 
inner surface is practically plane ; the dorsal and narrow two-thirds of the 
triangle is occupied by the elliptical scar of the posterior adductor muscle ; 
the anterior edge of this scar is smooth and forms the rim of the "shelf" ; 
from it a perpendicular wall descends to the floor of the visceral cavity. 
The ventral and wider one-third of the rostrum is the space for the siphon 
tubes, and is plane with the floor of the visceral space. 

From the lower end of the posterior adductor scar the narrow ribbon- 
like pallial line descends ventrally for a short distance, turns sharply pos- 

Weno and Pawpaw Formations 133 

teriorly and then makes an acute re-entrant angle (25 degrees) passing 
now anteriorly and almost perpendicularly to its former course; it runs 
in almost a straight line to the anterior one-third of the valve, where it 
gently curves upward meeting the postero-ventral corner of the scar of 
the anterior adductor muscle. 

This scar is roughly pear-shaped and its tip is continuous postero-dor- 
sally with an elevated ridge which passes along the bottom of the pit for 
the resilium. Dorsal to it, the elevated margin of the valve runs poster- 
iorly, stopping short at the middle of this pit. This pit is subcircular and 
lies anterior to the central tooth just dorsal to its mid-dorsal point is the 
umbo. Posterior to it is a circular elevation which is separated by a con- 
stricted neck from the post-adductor muscle scar. 

LOCALITY : Cut in Frisco railroad, three-fourths mile north of Union 
Station, Denison, Texas, in Weno marl, 20 feet below Quarry limestone 
(locality 604). 

PI. 10, fig. 5 

MEASUREMENTS: (Type) length of valve 18.0mm. 

Length of rostrum 4.0 mm. 

Height of valve _ 11.5 mm(?) 

HORIZON: "Buff marl," near middle of the Weno formation, and 
immediately below zone of abundance of Gervilliopsis invaginata (White) 
in association with Venericardia wenoensis, Trochus laticonicits, cidarid 
spines, Trigonia clavigera and Placosmilia sp. 

LOCALITY : 601, pit of brickyard, one and three-fourths miles south- 
east of Gainesville, Texas (type locality). 

A fragmentary right valve, lacking umbo, antero-dorsal margin and 
posterior half of ventral margin is apparently different from any other de- 
scribed species, and it is considered best to describe it here. The indi- 
vidual is rather similar to C. wenoensis Adkins. 

Right .valve, exterior: The (restored) contour is elongate-triangular, 
with probably a nearly straight antero-dorsal margin, a sharply rounded 
anterior angle (probably about 60 degrees), a long nearly straight ven- 
tral side, curving up only slightly to meet the ventral margin of the ros- 
trum. The rostrum is short, truncate, and the form of an isosceles tri- 
angle ; its rounded postero-ventral angle is 100 degrees ; its sharp postero- 
dorsal angle is 110 degrees; an almost obsolete shallow oblique groove 
separates it from the body of the valve, forming the base of the isosceles 
triangle. The postero-dorsal side is nearly straight except for a slight 

134 University of Texas Bulletin 

convexity in its posterior one-third. The valve is distinctly rotund and 

The ornamentation consists of 12 coarse rounded concentric ribs, and 
a number of fine growth lines in the umbonal region; the. ventral half of 
the height contains nine of the coarse ribs. These ribs turn dorsally along 
the anterior end of the rostrum and just posterior to the oblique shallow 
groove, making an angle of 95 degrees to 100 degrees. The ribs near 
this angle bear each about four or five fine growth lines. The edges of the 
ribs appear as thin slightly imbricated and overlapping lamellae. Dorsal 
to the angle, the rostrum is conically inflated, the width of the fold in- 
creasing postero-ventrally and at the posterior end occupying the whole 
height of the rostrum. Dorsal to the inflation is a narrow concurrent 
and slightly divergent depression. The rostrum is half the height of the 
shell and is very close to the ventral margin. The ribs are unbranched and 
continuous from the anterior to the posterior ends of the valve. They are 
elevated with rather sharply rounded tops and are separated by plane 
bottomed, vertical-sided valleys whose width is one-sixth that of a rib. 

Remarks: The following species of Corbula are to be found in the 
literature on the Comanchean : C. pikensis Hill (Trinity division) ; and 
C. crassicostata Cragin, Kiowa, Kansas, and (by implication) in the 
"ochreous shell-conglomerate of the Denison beds, Denison, Texas." 
C. basiniformis is distinguishable from the other species mentioned by its 
relatively unornamented surface and its geniculate margin. C. littoralis 
is distinguished from the others by its few coarse elevated and broad ribs ; 
C. wenoensis is distinguished from C. littoralis by its smaller size, its 
different and less elongate form, its greater number of ribs, the more dor- 
sal position of its rostrum, the shape and relative height and position of 
the rostrum, and by the internal characters as described. 


PI. 9, figs. 1-6 


MEASUREMENTS: PL 9, fig. 1 PL 9, fig. 4 PL 9,.fig. 2 

Height 52.0 52.0 76 

Length 58.5 59.0 77+ 

Breadth 15.0 17.5 25 

HORIZON: Weno formation, upper and middle thirds, shale facies. 

LOCALITIES : 604, cut of St. Louis and San Francisco Railway, one 
mile north of the Union Station, Denison, Texas (type locality) ; 601, pit 
of brickyards, three-fourths mile southeast of Gainesville, Texas. 

Weno and Pawpaw Formations 135 

DESCRIPTION: Shell subovate, inequilateral, subequivalve, beaks 
pointed anteriorly (prosogyrate) ; surfaces of both valves covered with 
numerous, simple, fine, striaeiform, concentric growth lines, and having a 
few widely spaced, coarser growth rings. Shell preserved, interior filled 
with ironstone. The beaks are inconspicuous, recurved anteriorly forming 
anterior to them a small notch in the margin and are rounded, incurved 
and approximate ; anterior to them the margins of the valves are in contact 
and the growth lines are imbricated and separated, making several lines 
parallel to the margins of the valves. Posterior to the beaks is a much 
wider triangular depression between the margins of the valve. It runs 
from the umbo backwards to the postero-dorsal, angle; its bottom is the 
apposed inner dorsal margins of the valves, its top the separated outer 
dorsal margins, while its sides consist of growth lamellae terminating 
abruptly and together constituting the thickness of the valves at this 
point. The groove in one individual contains over the medial half of its 
length a well preserved external hinge ligament. This has a chitinous 
appearance but is replaced by calcareous material. 

The dentition is approximately that of Cyprimeria Conrad. The hinge 
of the left valve consists of two posterior lamellae, two teeth and an an- 
terior lamella. The most dorsal posterior lamella is very broad and ob- 
lique, and is nearly parallel to the inner dorsal shell margin, which it has 
overgrown. It is roughly lanceolate or blade-shaped, the point being di- 
rected toward the umbo, the curved back directed ventrally, the edge di- 
rected dorsally and a narrowed portion directed postero-dorsally. It is 
separated by a narrow groove from the shorter second posterior lamella, 
which lies parallel to it and is coalescent with its umbonal half. Ventral 
to this lamella there is a narrow, deep, elongated pit, which separates it 
from the more posterior tooth. This pit in one individual contains a mass 
of brownish material chitinous in appearance but in fact calcareous. The 
two teeth are sharp, ridge-like and elongated, making an angle of about 
60 degrees with each other; they are remote and are separated by a tri- 
angular area, raised centrally. Running anteriorly from the base of the 
tooth is an elongate elevated margin which may be taken as an anterior 
lamella. Dorsal and parallel to this is an elongate groove which is bounded 
dorsally by the upturned inner dorsal edge of the valve. Parallel and an- 
terior to the anterior tooth is a narrow deeper depression the length of the 
tooth, which anteriorly connects with the groove. Below the teeth is an 
elongated area of small pits and punctations on the dorsal portion of the 
inner surface of each valve. Cyprimeria crassa Meek has been recorded 1 

'Hill, Annotated Check List, p. 14. 

136 University of Texas Bulletin 

from the Eagleford shales near Denison, Texas and Cragin considers it to 
be widespread in the Fredericksburg division in South Texas. This species 
is stated to differ from C. texana (Roemer) in its large thickness and size. 
Cragin 1 also records Cyprimeria sp. aff. excavata Morton from the Eagle- 
ford shales ("top of Ostrea quadriplicata beds"). Still a larger Cypri- 
meria, called C. gigantea* by Cragin is recorded from the Grayson marl 
near Roanoke, Texas ; we have found similar individuals in the Grayson 
at Roanoke, Denison, Burleson and elsewhere. Our species appears to be 
close to Cyprimeria texana (Roemer) which is known as casts from the 
Fredericksburg division. One individual of this species at hand shows a 
simple entire pallial line, some details of dentition, and papillae represeting 
the pits on the inner surface of the valves below the hinge, as mentioned 
above in the description of C. washitaensis and as figured by Roemer and 
Conrad for C. texana. The two species seem to differ but slightly, yet in 
view of the uncertain systematic position of the Fredericksburg species 
and its poor preservation it is thought best to describe the present material 
separately. The relations of the pallial line to the posterior adductor 
muscle scar are entirely different in the two species and the scar is of a 
different shape. In a fragment of the left valve of a large individual of 
C. washitaensis from near Denison the scar is subquadrate in shape and 
the pallial line attaches directly to its lower anterior corner, while in 
Roemer's figure 3 of the impression of the right valve, the scar is an inclined 
oval and its postero- ventral end lies in a prominent loop in the pallial line ; 
this loop is missing in our species. Roemer's species also appears to have 
a considerably sharper marginal curvature just anterior to the umbo than 
has C. washitaensis, of which however I have not yet found any interior 
casts for direct comparison, all of the known material consisting of nac- 
reous shells. 

PL 6, fig. 1 

This species does not have close similarities in form to that figured 
by Gabb," yet the hinge is rather similar. Stanton 5 has figured and dis- 
cussed the species of this genus. The hinge is here figured (PI. 6. fig. 1). 
The species has an acuminate tip, nearly straight antero-dorsal and postero- 
dorsal margins and a gently rounded ventral margin. Posteriorly the 

'Cragin, Geol. Surv. Texas, 4th Ann. Report., pp. 176-7, 1893. 

2 Cragin, Ibid., p. 176. 

sRoemer, Kr. Texas, pi. VI, fig. 8a. 

*Gabb, Geol. Surv. Calif., Pal. II, p. 270, pi. 36, figs. 17-17a, 1869 (Remondia furcata). 

5 Stanton, Proc. U. S. N. M., XIX, 299-301, 1920. 

Weno and Pawpaw Formations 137 

shell is incurved to form a rostrum-like constriction. There are 8 to 15 
roughly concentric, sharply elevated ridges which contract towards the 
posterior end of the shell. 

The species is occasional in the lower Weno marl of the Fort Worth 
region, especially at locality 618, in association with Pecten georgetown- 
ensis, Ancycloceras bendirei. Schloenbachia wintoni, Turritella worthensis, 
and Venericardia wenoensis. 



PI. 6, fig. 5 

MEASUREMENTS : ( Type individual ) . 

Height 21.0 mm. 

Breadth (estimated) 17.2 mm. 

Last whorl, height 11.0 mm*. 

Last whorl, breadth 10.0 mm. 

HORIZON: Basal stratum of Weno shale, in association with Ostrea 
quadriplicata, Gryphea washitaensis, Salenia sp. and various echinoids. 

LOCALITY: 606, just south of Frisco track, two and one-half miles 
north of Denison, Texas. 

DESCRIPTION : Shell conical, turreted, spiral angle about 63 degrees 
(estimated, shell of type distorted) ; volutions three or more, the terminal 
one being over one and one-half times the diameter of the next smaller one. 
Volutions angular, projecting, cross-section somewhat pentagonal. The 
volutions bear externally three coarse revolving ridges, of which the outer 
ones form the upper and lower shoulders of the volution. These ridges 
are equal and equally spaced, the distance between them being about two 
times the width of a ridge. The volution is crossed transversely by lan- 
ellar growth lines with thin overlapping irregular edges. From the center 
of the spire these trend sharply forwards, and crossing the first heavy ridge 
then pass obliquely across the outer face of the volution and after travers- 
ing the marginal strip of the volution on the other side of the ridges, dis- 
appear at the suture. They form slightly elevated imbricated low nodes 
on crossing the three spirals. Umbilicus absent, aperture indeterminate. 

138 University of Texas Bulletin 


PI. 10, figs. 30-31 


Height 9.0 7.8 

Greatest width 8.9 8.8 

Aperture, height 3.0 2.5 

Aperture, width 4.4 4.0 

HORIZON: Weno formation, shale facies. Has so far been found 
only in the zone of Gervilliopsis invaginata (White) . 

TYPE LOCALITY: 601, pit of brickyard, one and three-fourths miles 
southeast of Gainesville, Texas. 

DESCRIPTION: Shell small, conical, angulated. Volutions five of 
which, two earliest in this type, are nearly smooth. Form trochoid, apical 
angle 55 degrees, sutures impressed, ornamentation consists of a coarse, 
revolving spiral on the keel, ten finer spirals above, the alternate ones 
being coarser and consisting of equal low rounded tubercles, the others 
being straight fine revolving elevated ridges ; and below the keel ten eqaul 
similar non-tuberculate spiral ridges, each about half the width of the 
intervening valley. Growth lines numerous, fine, sigmoid, oblique to the 
ridges. Umbilicus concealed, small if any; aperture broken; probably 
obliquely oval. The next tuberculate ridge above the keel is thicker than 
the others and the keel and it lie just above the suture on the younger 
whorls and form a distinct angulation at the base of each volution. The 
shell on the last volution is thick (one half mm.) and the external markings 
well preserved. 

Trochus sp. Shattuck 1 from the Buda limestone at Austin differs from 
our species in having a larger apical angle (66 degrees) and straighter, 
non-angulated sides. Trochus texamts Roemer 2 from the Barton Creek 
(Austin, Texas) fauna of the Edwards limestone differs locally from our 
species in the nature of the ornamentation, the straightness of the sides 
and apparently in the shape of the aperture. This species is also described 
as having a pointed tooth on the inner margin of the outer lip. 

iShattuck, U. S. G. S. Bull. 205, p. 31, pi. XIX, figs. 2-3. 
2 Roemer, Pal. Abh., vol. 4, pt. 4, p. 15, pi. 1, fig. 13. 

Weno ami Pawpaw Formations 139 


1910: Helicocryptus mexicanus Bose, Inst. Geol. Hex., Bol. 25, p. 140, pi. 46, figs. 1-6; 
pi. 47, fig. 1. 

A single individual lacking the mouth but otherwise well preserved and 
agreeing with the original description, was determined by Dr. Bose as be- 
longing to this species. 

LOCALITY : 714, near Fort Worth, Texas, in the basal Pawpaw clay. 


PI. 10, fig. 28 

This fossil is found in the "buff marl" of the Weno brickyards at Gaines- 
ville, Texas, in association with Trochus laticonicus, Venericardia weno- 
ensis, and other fossils listed in the geological section of this locality. 

PI. 10, fig. 27 

This small calcitic fossil is one of a group of peculiar small fossils as- 
sociated in the "buff marl" of the brickyard pit, near Gainesville, Texas. 
The others are Trochus laticonicus Adkins, Nerita sp., Venericardia weno- 
ensis Adkins, Placosmilia spp., Trigonia clavigera Cragin, Leioddaris 
spines, Corbula littoralis Adkins, Pecten sp. and numerous widely distrib- 
uted Weno fossils. 


PI. 10, figs. 39-40 

1879: Anchura mudgeana White, llth Ann. Kept. Geol. and Geogr. Surv. Terr., p. 312, 

pi. 7, fig. 3a-b. 
1889: Anchura (Drepanocheilus) mudgeana Hill, Geol. Surv. Texas Bull. 4, p. 19. 

1894: Anchura mudgeana Hill, Bull. Geol. Soc. Amer., vol. 5, p. . 

1918: Anchura mudgeana Stephenson, U. S. G. S. Prof. Paper 120-H, p. 141. 

This common species of the Weno shale at Denison and Gainesville has 
not been found outside the Red River region, to my knowledge. It is con- 
spicuous in the ironstone and blue shale layers of the Weno in association 
with a large nacreous fauna including Corbula spp., Nucula spp., Turritella 
sp., Cerithium sp., Natica sp., and others. It differs from Anchura pro- 
labiata White in having a single instead of a double lip ; and from A. ruida 

140 University of Texas Bulletin 

White and A. haydeni White 1 in having a rounded, tabulated, externally 
directed lip instead of an upturned sharply pointed one. It differs from 
Anchura monilifera Gabb 2 found at Arivechi, Sonora, in the less elongate 
form and greater apical angle, in the greater width of the aperture, and 
in the tabulated lip. 


PI. 10, fig. 29 

A small nacreous Natica is known from the ironstone layers of the Upper 
Weno shale of the Red River region. It is preserved with the slightly 
altered calcareous shell. Locality 601, pit of brickyards near Gainesville, 

PI. 10, fig. 38 

This Weno species has a nacreous preservation and occurs in both the 
Upper Weno shale and the interspersed clay-ironstone seams. It is oc- 
cosional in the ironstone heap thrown out of the brickyards pit near Gaines- 
ville, Texas. 


PI. 10, fig. 41 

This large species is rare in the Red River region, and is known from 
the clay-ironstone layers of the upper part of the Weno shale, in associa- 
tion with Protocardia sp. aff. multristriata (Shumard), Turritella gray- 
sonensis, Cinulia washitaensis, Gervilliopsis invaginata, Schloenbachia win- 
toni, Cambarus ? sp. and other Upper Weno fossils. Locality, 601, near 
Gainesville, Texas. 


PI. 10, fig. 43 


Type, greatest height ----------------------- 36.0 mm. 

Width of last volution _______________________ 11.5 mm. 

Section of last volution, height _______________ 7.5 mm. 

Section of last volution, width ________________ 7.0 mm. 

e, llth Ann. Kept., U. S. G. and G. S. Terr., 1879. 
"Gabb, Geol. Surv. Cal., Pal. II, p. 262, pi. 35, fig. 7, 1869. 

Weno and Pawpaw Formations 141 

HORIZON: Weno shale and ironstone, abundant; Pawpaw clay and 
sand, rare. Rare south of the Red River region. 

LOCALITY : This is the common nacreous Turritella of the Weno iron- 
stone and clay at Denison, Gainesville, and elsewhere in the Red River 
region. Locality 604, Frisco cut three-fourths mile north of Union Sta- 
tion, Denison, Texas (type locality) ; 601, near Gainesville, Texas. 

DESCRIPTION: Shell turreted, steep, spiral angle 17 degrees; ten 
or more volutions, straight-sided, sutures sharply impressed, angles of 
volutions sharply rounded, surface almost smooth, bearing about fourteen 
lightly tuberculate spiral lines of unequal height. Of these, ten lie on 
the side of the volution and four below the shoulder. On the terminal 
volution of the type these are arranged as follows : 

Beginning at the suture, the first ridge is strongest and bears widely 
spaced low obscure tubercles with flat spaces between; the thickness of 
this rib equals the width of the space separating it from the second rib. 
The second, fifth and seventh ribs are slightly narrower, but are ribbon- 
like and low in proportion to their breadth and have slight nodular eleva- 
tions widely spaced from each other. The other ribs are low, subequal and 
have rounded tops and slight nodular elevations at wide intervals. The 
last four ribs lying beyond the shoulder of the volution are relatively nar- 
rower and more elevated than those on the flanks, and the inner three are 
closely spaced, being separated by about the width of a rib ; the last rib 
is more widely separated but is the same size. The rest of the volution 
next to the umbilicus is smooth except for one or two obsolete spiral ribs. 
In the intervals between the ribs mentioned there are three to five fine 
equal raised lines. The transverse growth lines are prominent and sig- 
moid, and resemble those in T. bravoensis Bdse, but are finer. Aperture 
unknown ; crass-section of volution sub-quadrate, outer side straight, inner 
side rounded. 

This species is separated from Turritella bravoensis Bdse, T. budaensis 
Shattuck, and T. planilateras Conrad by having the tubercles very low, 
and depressed, instead of coarse and prominent. It is separated from 
T. leonensis Conrad, T. marnochi White, and T. denisonensis Cragin in 
having a greater number of spiral ridges and more tubercles in each ridge. 

Cragin 1 describes without figuring, a variety under the name of T. kan- 
sensis, which has less crowded revolving ridges than our species. Like- 
wise, T. seriatim-granulata Roemer 2 differs from T. wenoensis in having 
only five elevated tuberculated ridges, the middle one of which is flanked 

iCragin, Notes on some fossils of the Comanche series, Science, n. s., vol. 6, pp. 134- 
136, 1897. 
zRoemer, Kr. Texas, p. 39, pi. 4, fig. 12. 

142 University of Texas Bulletin 

on each side by a low, non-tuberculate ridge. The ridges are wider and 
more prominent than in our species and the intervening spaces much nar- 
rower ; the tubercles are more widely spaced ; the fine secondary revolving 
lines are apparently lacking; and the contour is more angular. Roemer's 
species is also figured as having a smaller apical angle (about 12 degrees). 

PI. 10, fig. 42 

MEASUREMENTS: Type length of fragment 26 mm.; width (esti- 
mated) 14.5 mm. 

HORIZON: Basal Weno formation, marl facies. Abundant in the 
Fort Worth region in association with Ancycloceras bendirei, Remondia 
acuminata and Pecten georgetownensis. 

LOCALITIES: 618, near Fort Worth, Texas (type locality); exten- 
sively distributed in Tarrant County, Texas. 

DESCRIPTION: Shell conical, steeply turreted, apical angle 23 de- 
grees, with six or more volutions. Shell nearly straight sided, sutures 
impressed, surface with usually six nearly elevated spiral ridges bearing 
conspicuous, equal, equally-spaced, rounded tubercles. Beneath this are 
two parallel thin spiral ridges with obsolete tubercles. These form the 
bottom of the volution, and the uppermost of the six ridges mentioned, 
which is longer than the others, forms the top. Between each two ridges 
are four to six fine non-tuberculate spiral lines, but exceptionally one or 
two of these may be thickened, giving the appearance of an alternating 
series of fine and coarse revolving ridges on the volution. In most of the 
material at hand the six revolving ridges are equally spaced, and are sep- 
arated by a depression only slightly wider than one of the ridges. The 
tubercles are equally spaced on all the ridges, and number about 65 on 
the last volution. These tubercles decrease in size on the earlier volutions, 
and all are present in the youngest stage examined. 

Transverse growth lines are not visible. The details of the aperture 
are not preserved. The cross-section is rounded and triangular, the ex- 
ternal side of the volution being longest. Below the shoulder of the usually 
tuberculate volution are about four impressed lines, of which the two al- 
ready mentioned are not covered by the succeeding volution. Below this 
point the volution is smooth. 

Many species of Turritella have been described from the Texas Coman- 
chean, and some of these are indeterminate, on account oi faulty figures 
and description, or lack of necessary information concerning stratigraphy 
and locality. 

Weno and Pawpaiv Formations 143 

The present species is nearly straight-sided and is slightly angulated, 
while in T. bravoensis Bose 1 the middle rows of tubercles form a conspicu- 
ous angular projection on each volution. The number of rows of tubercles 
is greater than in Bb'se's species and the tubercles are more crowded in 
the rows. The conspicuous transverse striated growth lines of his species 
are absent in our material. T. pkmilateras Conrad 2 is somewhat similar 
in form to our species, but has a prominent alternation of tuberculate and 
smooth spiral ridges, while in our species the intermediate lines are tuber- 
culate and do not approach the main ridges in thickness. T. budaensis 
Shattuck 3 has the rows of tubercles diverse, the second row from the suture 
being most prominent, and the form is more angulated than in our species. 
T. worthensis is at once separated by its strong tubercles from the faintly 
tuberculate or granulated species, T. seriatim-granulata Roemer 4 (Freder- 
icksburg, Lower Washita), T. marnochi White, 5 T. leonensis Conrad (Fred- 
ericksburg) 6 and T. denisonensis Cragin 7 (Mainstreet, Grayson). 

Ellisor 8 has described several species of TurriteUa of which only T. man- 
chacensis (Buda) and T. washitensis (Buda> seem to approach the present 
species in ornamentation or form. 

PL 10, figs. 33-37 

1920: Cinulia sp. Winton and Adkins, Univ. Texas Bull. 1931, p. 66. 


Total height 15 mm. 

Total breadth . 14 mm. 

Body whorl, excluding lip, height 10 mm. 

Body whorl, excluding lip, breadth 10 mm. 

Breadth of lip 4 mm. 

HORIZON: Weno blue shale and clay-ironstone layers, middle and 
upper portions of the formation, especially in the Red River region. 
LOCALITY : 601, pit of brickyards, one and three-fourths miles south- 

ifiose, Inst. Geol. Mex., Bol. 25, p. 149, pi. 31, figs. 8-9; pi. 32, figs. 1-2, 1910. 

'Conrad, Mex. Bdry. Surv., Vol. 1, Pt. II, p. 158, pi. 14, figs, la-b, 1857. 

"Shattuck, U. S. G. S. Bull. 205, p. 31, pi. XIX, figs. 4-6, 1902. 

4 Roemer, Kr. Texas, p. 39, pi. 4, figs. 12a-b, 1852. 

'White, U. S. G. and G. S. Terr., llth Ann. Kept., pp. 314-315, pi. 7, figs. 5a-b, 1879. 

Conrad, Mex. Bdry. Surv., Vol. 1, Pt. II, p. 165, pi. 21, figs. 7a-b, 1857. 

'Cragin, Colo. Coll. Stud., 5, p. 65, 1895. 

"Ellisor, Univ. Texas Bull. 1840, 1920. 

144 University of Texas Bulletin 

east of Gainesville, Texas (type locality) ; 604, cut of St. Louis and San 
Francisco Railway, three-fourths mile north of Union Station, Denison, 
Texas. Occasional in Cooke and Grayson counties, Texas. About 25 in- 
dividuals found. 

DESCRIPTION : Shell of medium size, sub-globose, total outline sub- 
elliptical; four volutions, of which the last is much the largest and occu- 
pies two-thirds the height of the shell. Surface ornamented with evenly 
rounded equal revolving lines, about 25 on the last volution. Between 
the lines are concave depressions each about one and one-half times the 
width of a line. These contain numerous equally spaced vertical cross 
striations, which run perpendicular to the depressions and to the adja- 
cent revolving lines. Aperture elongate, rounded-cuneate, narrowed at 
the top and enlarged at the bottom. Outer lip much thickened and rounded, 
elongate, extending the length of the two last volutions in the type (slightly 
shorter in other individuals), and bearing on the inner margin about 14 
nearly equal blunt tubercles in two equal groups. The inner lip is flat 
and expanded and bears on its apertural margin three elevated spiral folds 
or laminae which project into the aperture ; these are thickened and rounded 
at their free margins ; the basal two lie almost horizontal while the upper 
one is directed somewhat downwards and is concealed underneath the 
jnner lip. Viewed from outside the outer lip is very broad and thick- 
ened and bears about seven irregular coarse overlapping laminae. 

This species resembles Cinulia tarrantensis Cragin 1 of the Goodland 
limestone near Fort Worth, but differs in several respects. C. tarrantensis 
is poorly described and figured and some of its critical points are inde- 
terminate, no further material having been discovered from the type 
locality, Goodland limestone near Benbrook, Tarrant County, Texas. The 
type apparently is lost, or at least it is not in the other Bumble Survey 
material at Austin. Cinulia is extremely rare in the Goodland limestone 
of the Fort Worth region. The species appears to differ from C. wash- 
itaensis in having a narrow and much less imbricate lip and in having 
the spire lower in proportion to the length of the lip. In Cragin's species 
the lip does hot seem to reach the top of the body whorl, while in the type 
of our species it is more elongate, extending the whole length of the term- 
inal and next adjacent whorls instead of only three-fourths of the term- 
inal whorl. In some other individuals it is lower, but never so low as in 
C. tarrantensis. The figure of C. tarrantensis shows the angulation of 
the turns above the body whorl to be pronounced, while in our species 
also differs in numerous details. The outer lip is broader in proportion 

Cragin, Geol. Surv. Texas, 4th Ann. Kept., p. 223, pi. XLII, fig. 1. 

Weno and Pawpaw Formations 145 

these turns are rounded. The shape of the aperture and of the teeth 
to the body and bears much coarser imbricated lamellae than in Cragin's 
species; the aperture is more slender throughout and is noticeably more 
compressed below; the sub-central crenulate region of the inner edge of 
the outer lip is distinctly angular ; the inner lip is broader and the three 
teeth placed differently, the two terminal ones being more closely spaced. 
Our species is apparently larger than C. tarrantensis, and comes from a 
higher horizon. 

The unfigured and indeterminate species Cinula ? texana (Shumard) 2 
was described from the Fredericksburg division of Bosque County; its 
description will apply to most species of the genus. C. rectilabrum Gabb 1 
is a lower species and bears on its inner lip two teeth instead of three; 
it is more slender, more pointed apically, and has narrower lips and a 
more elongate aperture. Cinulia pelletti Whitney and C. conradi Whit- 
ney, 3 both. from the Buda limestone differ in several respects from the 
Weno species, the former in the proportions of the shell, the height and 
shape of the aperture, and the thickness of the outer lip, the latter in the 
shape, size and number of costellae. 



PI. 11, fig. 2 

This characteristic foraminiferean shell has already been described* 
in some detail and the features mentioned apply to the Weno and Pawpaw 
material at hand. The fossil ranges in North Texas through the upper 
third of the Weno limestone and the base of the Pawpaw clay. The in- 
dividuals are generally scattered, but also rarely occur in slabs. At Fort 
Worth there is a zone of abundance at a point about 18 feet below the top 
of the Weno formation, which is found at this stratigraphic level every- 
where between the Red River and the Brazos. This zone appears to be 
different from the common Del Rio Nodosaria zone of West Texas, for 
prevailingly in West Texas the zone of abundance of Nodosaria is in the 
top of the Del Rio clay .iust underneath the Buda limestone, and the fossil 
is scattering in the middle Del Rio clay. Near Del Rio, Texas, where the 
formation is about 200 feet thick the Nodosaria slabs are prominent near 
the top, and near the Chisos Mining Company, Brewster County, where 

iGabb, Geol. Surv. Calif., Pal. II., p. 264, pi. 35, figs. 10-10a. 

'Shumard, Trans. Acad. Sci., St. Louis, I, 1860, 597. 

"Whitney, Trans. Texas Acad. Sci., XII, p. 23, pi. 10, figs. 9-11. 

B6se, Inst. Geol. Mex., Bol. 25, p. 177, 1910; Adkins and Winton, Univ. Texas Bull. 

1945, p. 76, 1920. 

146 University of Texas Bulletin 

the Del Rio clay is 120 feet or more thick, the zone of abundance of 
Nodosaria is above the occurrence of Exogyra cartledgei Bose, which lies 
10-30 feet below the Buda limestone. 1 This level probably corresponds 
to the Grayson formation of North Texas. Nodosaria is rare at Austin 
in the middle Del Rio clay. At Cerro de Muleros, which is in the northern 
facies, it is reported as occurring in subdivision 5 (Duck Creek and Fort 
Worth), and as abundant in subdivision 6 (Denton, Weno and Pawpaw) ; 
this is its lowest recorded occurrence. 3 


Adkins, W. S., and Winton, W. M.: Paleontological Correlation of the Fredericksburg 
and Washita Formations in North Texas. Univ. Texas Bull. 1945, 1920. (Bib- 

Berry, E. W. : The lower Cretaceous floras of the world. Maryland Geol. Surv., Lower 
Cretaceous, pp. 99-151. Baltimore, 1911. 

The upper Cretaceous floras of the world. Maryland Geol. Surv., Upper 

Cretaceous, pp. 183-313. Baltimore, 1916. 

Bose, Emil: Monografia geologica y paleontologica del Cerro de Muleros, etc. Inst. 
Geol. Mex., Bol. 25, 1910. 

On a new Exogyra from the Del Rio clay and some Observations on the 

Evolution of Exogyra in the Texas Cretaceous. Univ. Texas Bull. 190?, 1919. 

Cotteau, G.: Echinides, in Paleontologie francaise. 

Cragin, F. W. : A contribution to the Invertebrate Paleontology of the Texas Creta- 
ceous. Geol. Surv. Texas., 4th Ann. Rept., pp. 141-294. 

Descriptions of Invertebrate fossils from the Comanche Series in Texas, 

Kansas, and Indian Territory. Colo. Coll. Stud., 5, 1895, 49. 

Dumble, E. T.: The Geology of East Texas. Univ. Texas Bull. 1869, 1920 
Grossouvre, A.: Recherches sur la Craie Superieure. I. Stratigraphie generale. 

II. Paleontologie. Paris, 1893-1901. 
Haug, Emile: Traite de Geologic. Paris, 1911. 
Hill, R. T.: The Geology of the Black and Grand Prairies of Texas. U. S. G. S. 21st 

Ann. Rept., Pt. 7, 1901. 

Geology of the Territory adjacent to the Red River in Arkansas, Texas. 

and Indian Territory. Bull. Geol. Soc. Amer., 5, pp. 297-338, 1893. 

Noetling, F.: Die Fauna der baltischen Cenoman-geschiebe. Pal. Abh., BH. II. heft 4, 

Pervinquiere, L.: Etudes de paleontologie tunisienrie. I. Cephalopodes des terrains 

secondaires. II. Lamellibranches et gastropodes des terrains secondaires. Paris, 

Pervinquiere. L. : Sur quelques ammonites du cretace alger'en. Mem. Soc. Geol. France, 

Paleontologie, tome xvii, fasc. 2-3, Mem. No. 42, pp. 1-86, pis. 1-7 (x-xvi), 1910. 

'Bose, Univ. Texas Bull. 1902, p. 19, 1919. 
-Bose, Inst. Geol. Mex., Bol. 25, pp. 24-26, 1910. 

Weno and Pawpaw Eormations 147 

Richardson, G. B.: Report of a reconnaissance in Trans-Pecos Texas north of the 

Texas and Pacific Railway, Univ. Texas Mineral Surv., Bull. No. 9, 1904. 
Sayn, G. : Les ammonites pyriteuses des marnes valangiennes du sud-est de France. 

Mem. Soc. Geol. France, Paleontologie, tome 9, Mem. No. 23, pis. 1-6 (vi-x, pi. vii 

repeated), pp. 1-66, 1901. 
Sellards, E. H.: The Geology and Mineral Resources of Bexar County. Univ. Texas 

Bull. 1932, 1920. 
Sladen, P., and Spencer, W. K. : A monograph of the British fossil Echinodermata, 

Asteroidea. Paleontogr. Soc. 
Szajnocha, Ladislaus: Zur Kenntniss der mittelcretacishen Cephalopodea-fauna der 

Inseln Elobi an der Westkiiste Afrika. Denkschr. d. Kais. Akad. Wiss., Wien., 

XLIX, pp. 1-8, pis. 1-4, 1884. 

Whitney, F. L.: The Echinoidea of the Buda limestone. Bull. Amer. Pal., No. 26, 1916. 
Winton, W. M., and Adkins, W. S.: The Geology of Tarrant County. Univ. Texas 

Bull. 1931, 1920. 


Flickia, Schloenbachia, Mortoniceras, Acanthoceras 

150 University of Texas Bulletin 


Flickia, Schloenbachia, Mortoniceras, Acanthoceras Plate 1 

Figures 1-3. Flickia boeei n. sp Page 85 

Rare, basal Pawpaw formation, marl-clay transitional area. Fig. 1, type indi- 
vidual, side view, x 4.7; fig. 2, same individual, ventra' view, x 4.7; fig. 3, 
same individual, x 1.33. Locality: 714, near Fort Worth, Texas. 

Figure 4. Flickia (?) bosquensis n. sp Page 87 

Rare, top of Exogtfra arietina horizon, middle Del Rio clay (equivalent of base 
of the Grayson formation). Locality: cliff on west bank of the South Bosque 
River, 100 yards south of the bridge of the Speegleville road, and 5.5 miles 
west of the courthouse at Waco, Texas. Type individual, side view, x 2.0. 
(See PI. 4, fig. 11.) 

Figure 5. Schloenbachia sp 

Rare, basal Pawpaw clay. Locality: 714, near Fort Worth, Texas. 

Figures 6-10, 18-19, 26. Mortoniceras worthense n. sp Page 91 

Abundant, Pawpaw formation, base, clay facies. 

Fig. 19, type individual, x 4.0. Locality: 723, near Fort Worth, Texas; figs. 10, 
26, same locality, x 4.0. Other figures, x 2.0, same locality. 

Figures 11-13, 15-17, 20-25. Acanthoceras worthense n. sp Page 93 

Abundant, Pawpaw formation, base, clay facies. 

Fig. 12, type individual, x 2.0. Locality: 723, near Fort Worth, Texas. Other 
individuals, x 2.0, same locality. 

Figure 14. Schloenbachia wenoensis n. sp Page 89 

Rare, Pawpaw formation, base, clay facies. Fig. 14, type individual, x 2.0. 
Locality: 723, near Fort Worth, Texas. 

University of Texas Bulletin No. 1856 

Scaphites, Hamulina, Metopaster, Comptonia 

152 University of Texas Bulletin 


Scaphitei, Baculites, Ptychoceras, Metopaster, Comptonia Plate 2 

Figures 1-12. Scaphites hilli Adkins and Winton Page 79 

Occasional, basal 10 feet of the Pawpaw formation, clay facies, sparse outside of 
Tarrant County region. Fig. 1, type individual, x 4.0, ventral view, showing 
suture and mid-ventral groove. Locality: 714, near Fort Worth, Texas. Fig. 
2, individual showing venter with sutures outlined in the hematite and limo- 
nite areas, x 4.0. Locality: 714. Fig. 3, individual showing suture, dorso- 
lateral tubercle, and aperture, x 4.0. Locality: 714. Fig. 4, same individual, 
reverse side, x 6.0. Figs. 5, 6, individuals x 4.0. Locality: 714. Fig. 7, indi- 
vidual showing uncoiled portion and dorso-lateral tubercle, x 2.0. Locality: 
723, near Fort Worth, Texas. Fig. 8, individual showing uncoiled portion, 
tubercle and juvenile suture, x 4.0. Locality: 723. Figs. 9-12, showing rib 
variations, x 4.0. Locality: 723. 

Figures 13, 15-18. Scaphites sp. aff. hilli Adkins and Winton 

Occasional, Pawpaw clay, base. Fig. 14, x 3.0; figs. 13, 16-18, x 2.0, showing rib 

variations. Locality: 713, near Fort Worth, Texas. 

Figure 14. Metopaster hortensae Adkins and Winton Page 97 

Rare, Pawpaw formation, base, clay facies. Type individual, aboral side, x 2.0. 
Locality: 714, near Fort Worth, Texas. 

Figure 19. Comptonia wintoni n. sp Page 97 

Rare, Pawpaw formation, base, clay facies. Type individual, aboral side, x 3.0. 
Locality: 714, near Fort Worth, Texas. 

Figures 20-22. Baculites comanchensis n. sp Page 74 

Occasional, Pawpaw formation, base, clay facies. Type individual. Fig. 21, x 4.0. 
Locality: 719, near Fort Worth, Texas. Fig. 20, x 2.0, same locality. Fig. 21, 
x 2.0. Locality: 714, near Fort Worth, Texas, 

Figures 23-26. Hamulina worthensis n. sp Page 71 

Rare, basal Pawpaw clay. Type individual, Fig. 26, x 5.0, showing suture. 
Locality: 714. Fig. 23, individual showing form of curve and short limb, 
x 4.0. Locality: 714. Fig. 25, same individual, ventral view, x 2.0. Fig. 24, 
individual showing form of long limb and of curve, x 4.0. Locality: 714. 
Individuals of Figs. 23, 24 in museum of Texas Christian University, Fort Worth, 

University of Texas Bulletin No. 1856 

Plate 2 


Turrilites, Acanthoceras, Schloenbachia 


University of Texas Bulletin 


Turrilites, Acanthoceras, Schloenbachia Plate 3 

Figures 1, 6. Turrilites worthensis Adkins and Winton Page 78 

Abundant, Pawpaw formation, base, clay facies. Fig. 1, x 4.0; locality: 714, 

near Fort Worth, Texas. Fig. 6, showing portion of suture, x 4.0; locality: 

714, near Fort Worth, Texas. 

Figures 2, 4. Turrilites sp Page 78 

Abundant, Pawpaw formation, base, clay facies. x 4.0; locality: 714, near Fort 
Worth, Texas. 

Figures 3. 7. Turrilites bosquensis n. sp Page 76 

Rare, top of Exogyra arietina horizon, middle Del Rio clay (equivalent of base 
of the Gray son formation). Locality: cliff on west bank of the South Bosque 
River, 100 yards south of the bridge of the Speegleville road, and 5.5 miles 
west of the courthouse at Waco, Texas. Fig. 3, type individual, x 4.0, show- 
ing tubercles and angularity of profile. Fig. 7, same individual, x 2.0, show- 
ing aperture. 

Figure 5. Acanthoceras worthense n. sp Page 93 

Abundant, basal and middle Pawpaw clay. Individual showing venter, x 4.0. 
Locality: 714, near Fort Worth, Texas. 

Figures 8-11. Schloenbachia wintoni n. sp. . . Pag* 90 

Occasional, Pawpaw formation; abundant, Weno formation. Figs. 8, 11, type 
individual, x 1.0; locality 601, near Gainesville, Texas, nacreous individual 
from ironstone in upper third of Weno formation. Figs. 9-10, nacreous indi- 
vidual, x 1.0, same locality. Fig. 9 shows the slightly bifid marginal tubercles. 
Type in museum of Texas Christian University, Fort Worth, Texas. 

University o.' Te as Lulletin No. 1856 

Plate 3 


Schloenbachia, Engonoceras, Flickia, Corbula 

166 University of Texas Bulletin 


Schloenbachia Engonocreas, Flickia, Corbula Plate 4 
figure 1. Schloenbachla sp 

Rare, Pawpaw clay, x 4.0. Locality: 714, near Fort Worth, Texas. (See PI. 1, 
fig. 6.) 


Figure 2. Engonocerai sp Page 85 

Rare, Pawpaw clay, x 2.5. Locality: 714, near Fort Worth, Texas. 

Figure 4. Acanthocera* wortheiue n. sp Page 93 

Abundant, Pawpaw clay, x 4.0. Locality: 714, near Fort Worth, Texas. 

Figures 3, 5-6, 12. Engonoceras serpentinum (Cragin) Page 84 

Occasional, Weno shale, Grayson and Cooke counties, Texas and southern Okla- 
homa; rare, Pawpaw clay and shale. Figs. 3, 5, x 2.5; locality: 714, near 
Fort. Worth, Texas. Figs. 6, 12, x 1.0; locality: 604, near Denison, Texas. 

Figures 8-10. Engonoceras sp Page 85 

Very abundant, Pawpaw clay, especially near the base; rare, Grayson, Denton, 
and Duck Creek formations, clay and marl facies, x 3.0, locality: 714, near 
Fort Worth, Texas. 

Figure 11. Flickia (?) bosquensi* n. sp Page 87 

Rare, top of Exogyra arietina horizon, middle Del Rio clay (equivalent of base 
of Grayson formation). Type individual, x 4.0. Locality: cliff on west bank 
of South Bosque River, 100 yards south of the bridge of the Speegleville road, 
and 5.5 miles west of the courthouse at Waco, Texas. (See pi. 1, fig. 4.) 

University of Texas Bulletin No. 1856 



Hemiaster, Epiaster, Enallaster 

158 University of Texas Bulletin 


Hemiaster, Epiaster, Enallaster Plate 5 

Figures 1-2, 4. Hemiaster calvini Clark Page 114 

Occasional, Weno and Pawpaw formations; rare, Denton and Mainstreet forma- 
tions; abundant, middle Grayson formation. Fig. 1, large sized individual with 
strongly developed ambulacral grooves, x 2.0; locality: Argyle, Texas, Gray- 
son marl, Baylor University Museum. Fig. 2, individual in some respects re- 
sembling Hemiaster bexwi Clark, x 3.0; locality: 720, basal Pawpaw marl, 
near Riovista, Texas. Fig. 4, x 2.0; locality: west branch of Little Mineral 
Creek, one mile northeast of Fink, Texas. 

Figure 3. Enallaster wenoensis n. sp Page 112 

Abundant, Weno formation, marl facies; rare, Pawpaw formation, marl and clay 
facies. Type individual, x 4.0; locality: 720, basal Pawi.iaw marl, near Rio- 
vista, Texas. 

Figure 5. Epiaster aguilerae Bose Page 109 

Rare, basal Fort Worth limestone. Locality: 406, one-half mile east of Texas 
Christian University, Fort Worth, Texas. Aboral side, x 1.0. 

Univeriity of Texas Bulletin No. 1856 

Plate 5 


Remondia( ?), Venericardia, Amberleya, Hemiaster, E piaster 

160 University of Texas Bulletin 


Remondia, Venericardia, Amberleya, Hemiaster, Epiaster Plate 6 

Figure 1. Remondia (?) acuminata (Cragin) Page 136 

Occasional, basal Weno marl; rare, Pawpaw clay. Locality: 618, near Fort Worth, 
Texas, individual, x 1, showing hinge structure. 

Figure 2. Venericardia wenoensis n. sp Page 125 

Occasional, Weno formation, shale facies, Red River region, and marl facies, 
Fort Worth region. Fig. 2, individual, x 2.0, showing ribbing. Locality: 618, 
near Fort Worth, Texas. 

Figure 3. Hemiaster calvini Clark Page 114 

Occasional, Weno and Pawpaw formations. Fig. 3, x 3.0. Locality: 903, Gray- 
son marl, one-half mile southeast of Denison, Texas. 

Rare, basal Pawpaw formation, clay-marl transition area; rare, Weno marl. 
Type individual, x 4.0. Locality: 720, near Riovista, Texas. 

Figure 4. Hemiaster riovistae n. sp Page 115 

Rare, Weno formation, shale facies. Locality: 606, basal stratum of Weno form- 
ation, near Denison, Texas. Type individual, x 2.0, showing carinae and 

Figure 5. Amberleya graysonensis n. sp Page 137 

Abundant, basal Weno formation, marl facies; rare Pawpaw clay and marl. 
Type individual, x 1.0. Locality: 618, near Fort Worth, Texas. 

Figure 6. Epiaster wenoensis n. sp Page 105 

Abundant, basal Weno formation, marl facies; rare, Pawpaw clay and marl. 
Type individual, x 1.0. Locality: 618, near Fort Worth, Texas. 

University of Texas Bulletin No. 1856 

Plate 6 

Pentaceros, Comptonia, Metopaster, Pentagonaster 

162 University of Texas Bulletin 


Pentaceros, Comptonia, Metopaster, Pentagonaster Plate 7 

Figures 1-3. Pentaceros americanus n. sp Page 99 

Pawpaw formation, clay facies, basal 5 feet, rare. 

Fig. 1. Type individual, aboral side, x 2. Locality: 714, one-fourth mile south 

of the International and Great Northern Railway bridge across Sycamore 

Creek, four and one-half miles southeast of Fort Worth, Texas. The large 

~ plate above and to the left of the center of the disk is the madreporite. Type 

in museum of Texas Christian University, Fort Worth, Texas. 
Fig. 2. Type individual, oral side, x 2. 
Fig. 3. Type individual, aboral side, x 1.5. 

Figures 4-5. Comptonia wintoni n. sp Page 97 

Pawpaw formation, clay facies, basal portion, rare. 

Fig. 4. Type individual, aboral side, x 2. Locality: 714, near Fort Worth, Texas. 

Fig. B. Type individual, oral side, x 2. 

Figure 6. Metopaster hortensae Adkins and Winton Page 97 

Pawpaw formation, clay facies, base, rare. 

Type individual, oral side, x 2. Locality: 714, near Vort Worth, Texas. 

Figure 7. Pentagonaster texensis Adkins and Winton Page 95 

Weno formation, limestone facies, upper 10 feet, rare 

Locality: 602, east bank of Sycamore Creek, about four miles Southeast of Fort 

Worth, Texas. Aboral side, x 1.5. Figured individual in museum of Texas 

Christian University, Fort Worth, Texas. 

University of Texas Bulletin No. 1856 

Plate 7 


164 University of Texas Bulletin 


Hemiaster, Epiaster, Enallaster. Plate 8 

Figure 1. Hemiaster longisulcus (Adkins and Winton) 

Occasional, top of Fort Worth limestone. 1/pe individual, x 2.0. Locality: On 
Cedar Creek, two miles southeast of Blum, Texas. Note the similar pores of 
the anterior unpaired ambulacrum, and the posteriorly placed apical system. 

Figures 2-3, 5. Hemiaster riovistae n. sp Page 115 

x 2.0. Locality: 720, near Riovista, Texas. 

Figure 4. Enallaster bravoensis Bosc Page 114 

Occasional, Weno formation, marl and clay facies; rare, Pawpaw, Mainstreet and 
Buda formations; abundant, Grayson formation, marl and clay facies. Fig. 4, 
individual x 2.0. Locality 618, near Fort Worth, Texas. 

Figure 6. Hemiaster calvini Clark Page 114 

Locality unknown, Cummins Collection. Note position of apical system, and the 
deep ambulacra! grooves. 

Figure 7. Epiaster aguilerae Bose Page 109 

Rare, basal Fort Worth limestone. Locality: 406, one-half mile east of Texas 
Christian University, Fort Worth, Texas. (Same individual as PL 5, fig. 5.) 
Apical system, x 4.0. 

University of Texas Bulletin No. 1856 

Plite 8 


Cyprimeria, Corbula 

166 University of Texas Bulletin 


Cyprimeria, Corbula Plate 9 

Figures 1-6. Cyprimeria washitaensis n. sp Page 134 

Occasional, Weno shale, Cooke and Grayson counties, Texas Fig. 1, type indi- 
vidual, x 1.0; locality: 604, near Denison, Texas. Figs. 2-4, x 1.0, same locality. 
Figs. 3-5, individuals showing hinge structure, x 1.0, same locality. Fig. 6, 
individual showing posterior adductor muscle scar and part of pallial line, 
x 1.0, same locality. 

Figures 7-24. Corbula basiniformU n. sp Page 130 

Abundant, Weno shale and ironstone. Cooke and Grayson counties, Texas and 
southern Oklahoma. Fig. 21, type individual, x 1.5; locality: 604, near Den- 
ison, Texas. Other individuals, x 1.5, same locality. 

University of Texas Bulletin No. 1856 

Plate 9 



Corbula, Area, Protocardia, Neritina, Nerita, Natica, Lunatia, 
Trochus, Anchura, Cinulia, Globiconcha, Turritella 

168 University of Texas Bulletin 

PLATE 10. 

Corbula, Nucula, Area, Protocardia; Neritina, Nerita, Natica, Lunatia, Plate 10 

Trochus, Anchura, Cinulia, Globiconcha, Turritella 

Figures 1-4. Corbula wenoeiuU n. sp Page 127 

Weno shale, rare. Fig. 4, type. All individuals x 1.5. Locality: 601, pit of 
brickyards, one and three-fourths miles southeast of Gainesville, Texas. 

Figure 5. Corbula littoralis n. sp : Page 133 

Weno shale, rare. Fig. 5, type individual, x 1.5. Locality: 601, pit of brick- 
yards, one and three-fourths miles southeast of Gainesville, Texas. 

Figure 6. Area wasbitaensi* n. sp Page 121 

Abundant, Pawpaw clay; rare, Grayson, Den ton and Duck Creek formations, clay 
facies and more rare in the marl facies. Fig. 6, type individual, x 1.5. 
Locality: 714, one-fourth mile south of the International and Great Northern 
Railway bridge across Sycamore Creek, near Fort Worth, Texas, at the base 
of the Pawpaw clay. 

Figures 7-9. Corbula basiniformis n. sp Page 130 

Abundant, Weno shale. Locality: 604, cut of St. Louis and San Francisco Rail- 
way, one mile north of Union Station, Denison, Texas. (See PI. 9, figs. 7-24.) 
x 1.5. 

Figures 10111. Nucula wenoentis n. sp Page 120 

Rare, Weno shale. Fig. 10, type individual, x 1.5. Fig. 11, x 1.5. Locality: 601, 
pit of brickyards, one and three-fourths miles southeast of Gainesville, Texas. 

Figures 12-16, 19-20. Nucula nokonu n. sp Page 118 

Occasional, Weno shale, x 1.5. Locality: 604, near Denison, Texas. Type, Fig. 
19, x 1.5, same locality. 

Figures 21-26, 32. Protocardia sp. aff. multistriata (Shumard) Page 126 

Abundant, Weno ironstone and shale, x 1. Locality: 601, near Gainesville, Texas. 

Figure 27. Neritina sp Page 139 

Rare, middle Weno shale (buff marl). Locality: 601, near Gainesville, Texas. 

Figure 28. Nerita sp Page 139 

Rare, middle Weno shale. Locality: 601, near Gainesville, Texas, x 1.5. 

Figure 29. Natica sp Page 140 

Rare, ironstone and upper Weno shale. Locality: 601, near Gainesville, Texas. 

Weno and Pawpaw Formations 169 

Figures 30-31. Trochu* laticonicut n. sp. . Page 138 

Rare, middle Weno shale (buff marl). Locality: 601, near Gainesville, Texas. 
Fig. 30, type individual, x 1.6. Fig. 31, x 1.5. 

Figures 33-37. Cinulia washitaensii n. sp Page 143 

Occasional, middle and upper Weno shale. Locality: 601, near Gainesville, Texas. 
Fig. 33, type individual, x l.B. Figs. 34-37, x 1.5. 

Figure 38. Lunatia sp Page 140 

Rare, Weno ironstone and upper Weno shale. Locality: 601, near Gainesville, 
Texas. x 1.5. 

Figures 39-40. Ancjiura mudgeana White Page 139 

Abundant, middle and upper Weno shale, Cooke and Grayson counties, Texas. 
Locality: 604, near Denison, Texas, x 1.5. 

Figure 41. Globiconcha sp Page 140 

Rare, Weno ironstone. Locality: 601, near Gainesville, Texas, x 1.5. 

Figure 42. Turritella worthensis n. sp Page 142 

Abundant, lower Weno marl, Tarrant County, Texas. Type. Locality, 618, near 
Fort Worth, Texas. Fig. 42, type invidual, x 1.5. 

Figure 43. Turritella grayioneniis n. sp Page 140 

Abundant, Weno shale, Grayson County, Texas; occasional, Cooke County, Texas. 
Locality: 604, near Denison, Texas. Type, Fig. 43, x 1.5. 

University of Texas Bulletin No. 1856 

Plate 10 



Pecten, Epiaster, Nodosaria, Ancycloceras 

172 University of Texas Bulletin 

PLATE 11. 

Pecten, Epiaster, Nodosaria, Ancycloceras. Plate 11 

Figure 1. Ancycloceras bendirei n. sp Page 70 

Rare, Weno formation, base, marl facies. Fig. 4, type individual, x 1.2. Locality: 
618, near Fort Worth, Texas. 

Figure 2. Nodosaria texana Conrad Paije 145 

Abundant as isolated individuals and rarely in slabs, upper third of Weno and 
base of Pawpaw formations in north central Texas; abundant in flag layers, 
upper and to a less extent the middle Del Rio clay in West Texas. Fig. 3, 
x 5.0. Locality: Terlingua, Texas. (Compare Univ. Texas Bull 1945, pi. 21.) 

Figure 3. Epiaster subobesus n. sp Paga 110 

Occasional, Weno formation, marl facies, and Pawpaw formation, marl facies. 
Abundant near base of Weno, in the "first terrace" of the Fort Worth region. 
Fig. 2. Locality: 618, near Fort Worth, Texas, type individual, x 1.0. 

Figure 4. Pecten inconspicuus Cragin Page 12.3 

Abundant, Weno shales and ironstone; rare, Denton clay; rare, Pawpaw forma- 
tion, sand and ironstone facies. Cooke and Grayson counties, Texas, and 
southern Oklahoma. Fig. 1, clay-ironstone shell conglomerate from the middle 
Weno shales, x 4.0. Locality: 604, near Denison, Texas. 

University of Texas Bulletin No. 1856 

. .' 

On A New Ammonite Fauna of the Lower Turonian 

of Mexico 


Emil Bbse 

176 University of Texas Bidletin 

Exogyra Say 230 

Exogyra haarmanni sp. nov 230 

Exogyra of r. olisiponensis Sharpe 230 


Tylottoma Sharpe 232 

Tylostoma aff . ovatum Sharpe 232 


Hemiaster Desor 232 

Hemiaster sp 232 


Figure 1. Metoecocerai aff. white! Hyatt, suture 204 

Figure 2. Suture, Vatcocera* angermanni i. sp. (above) and Vascocerat aff. 

adonense Choffat (below) 216 

Figure 3. Suture, Va.cocera. aff. gamai Choffat 21G 

Figure 4. Sutures, Vascocera* mohovanenie n. sp. (above) , and Mammite* 

mohovaensi* n. sp. (below) 220 

Figure 5. Suture, Neoptychite* aff. cephalotu* Courtiller 222 

Figure 6. Suture, Neoptychite* aff. cephalotu.- Courtiller 222 

Figure 7. Sutures, Neoptychite* aff. xetriformU Pervinquiere (lower left hand 

corner) and Hoplitoide* sp. (other three) 226 

Plates 12-20. Lower Turonian Fossils from Cerro del Macho.. ..235-252 






A number of years ago the existence of Turonian beds was proven in 
Mexico and later on it was shown that these beds have a great distribu- 
tion in the country. At first very few localities with faunas of this age 
were known, but later the finds of fossils of Turonian age have augmented 
in such a manner that we now know that the Turonian has a vast dis- 
tribution in Mexico, numerous localities having been discovered between 
Lat. 2030' N. and Lat. 32 N. All of these beds are petrographically 
very uniform and consist of argillaceous shales and laminated limestones 
with intercalations of thin beds of limestone, all of black to light gray 
color. The fauna of these beds is also rather uniform and consists mostly 
of numerous specimens of Inoceramus labiatus Schlotheim, in some places 
accompanied by Inoceramus hercynicus Petraschek ; in some localities fishes 
are relatively numerous ; in others bivalves other than Inoceramus are 
found. Cephalopods have been found very rarely, all of them crushed 
and nearly indeterminable. The determination of the age had to be 
founded exclusively on the Inoceramus and on the position of the beds 
in relation to the Senonian and the Cenomanian. 

About nine years ago I received the first collections of Turonian am- 
monites, which allowed a much better determination of the age of the 
beds mentioned here because these cephalopods were found together with 
well preserved specimens of the same Inoceramus which already had been 
determined by us as 1. labiatus. 

In February, 1911, Dr. Ernst Angermann sent me a email collection 
of fossils collected by him on the Cerro del Macho, Hacienda del Moh6vano, 
Municipality of San Pedro, District of Parras in the State of Coahuila. 
The greater part of these fossils consisted of internal molds of bivalves 
and gastropods, but there were also present three cephalopods relatively 
badly preserved and several indeterminable fragments of ammonites. I 
recognized at once that these fossils belonged to a facies and a horizon 
altogether unknown in Mexico, one of the ammonites being a Vascoceras 
of the group of V. Kossmati and another a Neoptychites of the group of 
N. xetriformis Pervinquiere, the bivalves belonged mostly to Trigoniu, 

180 University of Texas Bulletin 

Avicula of the group of A. gravida Coquand, the gastropods to Tylostoma 
and similar genera. 

A short time afterwards I showed these fossils to Dr. E. Haarmann, 
geologist of the Cia. Perforadora Mexicana, who then told me that he had 
a much larger collection of fossils from the same locality which he had 
made before Dr. Angermann had visited the place ; and he offered me his 
material for a detailed paleontological study. The collection of Dr. Haar- 
mann proved to be much larger than that of Dr. Angermann and con- 
tained a large number of ammonites some of which were rather well 
preserved. Haarmann in making his collection had separated the fos- 
sils of the different beds. The lowest of these beds was represented by 
a single piece of rock with impressions of bivalves, but as this rock had 
a very distinct character from that of the other beds and as in a locality 
of apparently the same age a badly preserved sea urchin had been found 
which appeared to belong to Hemiaster, I asked Dr. Haarmann to collect 
better material in the lowest horizon, because this horizon seemed to be- 
long to the Cenomanian. Haarmann visited the locality again in August, 
1911, collected ammonites in each of the three beds distinguished by him, 
and turned this material over to me in April, 1912. 

The material thus collected proved to be of great stratigraphical and 
paleontological interest, as will be shown by the following description. 
But before I enter into a detailed study I wish to express my gratitude 
to Dr. E. Haarmann to whose amiability I owe the opportunity of studying 
this interesting fauna. I also wish to express my obligations to Professor 
Dr. W. Branca in Berlin who kindly sent me a great number of photo- 
graphs of Turonian ammonites from Egypt, studied by Dr. Eck but at 
that time still undescribed. 


1. Boule, Lemoine et Thevenin, Diego Suarez. M. Boule, P. Lemoine et A. Thevenin, 

Paleontologie de Madagascar. Cephalopodes cretaces des environs de Diego- 
Suarez. Ann. de Palontologie t. I et II, Paris, 1906-07. 

2. Choffat, Especes nouv. ou peu conn. P. Choffat, Recueil d'etudes paleontologiques 

sur la faune cretacique du Portugal. Vol. L, Especes nouvelles ou peu 
connues. Ire. serie. Section des Travaux geologiques du Portugal. Lisbon, 

3. Choffat, Syst. cret. Portugal II. P. Choffat, Recueil de Monographies strati- 

graphiques sur le systeme cretacique superieur au nord du Tage. Service 
geol. du Portugal. Lisbonne, 1900. 

4. Chudeau, Ammonites du Damergou. R. Chudeau, Ammonites du Damergou 

(Sahara meridional). Bull. Soc. geol. France, 4me ser., t. 9, fasc. 1-2, 1909. 

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de la region sud de la Province de Constantine. Mem. Soc. d'Emulation de 
la Provence, II. Marseille, 1862. 

A New Ammonite Fauna of the Lower Turanian of Mexico 181 

6. Cotteau, Peron et Gauthier, Ech. foss. de 1'Algerie. Cotteau, Peron et Gauthier, 

Echinides fossiles de 1'Algerie. Description des especes deja recueillies das 
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manien. Paris, 1878. 

7. Eck, Turon in Aegypten. O. Eck, Vorlaufige Mitteilungen tiber die Bearbeitung 

der Cephalopoden der Schweinfurthschen Sammlung und Uber die Entwick- 
lung des Turons in Aegypten. Monatsber. d. Deutsch. Geol. Ges. 1910. Ber- 
lin, 1911. 

8. Fourtau, Faune cret. d'Egypte. R. Fourtau, Contribution a 1'etude de la faune 

cretacique d'Egypte. Bull. Institut Egyptien, ser. 4, vol. 4, 1903. 

9. Fritsch, Ceph. bohm. Kreideform. A. Fritsch, Cephalopoden der bohmischen 

Kreideformation (unter Mitwirkung des Dr. Urb, Schlonbach). Prag, 1872. 
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eontographia Bd. 20, I u. II. 1872-75. 

12. Gueranger, Album Paleontol. Ed. Gueranger, Album Paleontologique de la 

Sarthe representant au moyen de la photographic les fossiles recueillis dans 
cette circinscription. Le Mans, 1867. 

13. Guillemain und Harbort, Profil d. Kreidesch. a. Mungo. C. Guillemain und E 

Harbort, Profil der Kreideschichten am Mungo. Abh. d. k. Preuss. Geol. 
Landesanstalt Neu Folge, Heft 62, 1909. 

14. Haug, Traite de Geologic. Paris, 1908-11. 

16. Hyatt, Pseudocer. A. Hyatt, Pseudoceratites of the Cretaceous. Edited by T. W. 
Stanton. U. S. Geol. Surv. Monogr. vol. 44, Washington, 1903. 

16. Jack and Etheridge, Queensland. R. L. Jack and R. Etheridge, Jr. The Geology 

and Paleontology of Queensland and New Guinea. Brisbane and London 

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Ueber Fossilien der Unteren Kreide am Ufer des Mungo in Kamerun. Abh. 
K. Ges. d. Wiss. zu Gottingen, Math. Phys. Kl. Neue Folge, Bd. 1, No. 1 

18. Kossmat, Stidind. Kreideform. Fr. Kossmat, Untersuchungen uber die sudin- 

dische Kreideformation. Beitrage zur Palaeontologie und Geologie Oester- 
reich-Ungarns und des Orients, I Bd. 9, 1895; II u. Ill Bd. 11, 1897. 

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et des contrees avoisinantes telles que 1'figypte et PArabie. II me partie 
Paleontologie. Ann. d. Sciences Geologiques publ. s. 1. dir. de M. Hebert et 
A. Milne-Edwards. T. III. Paris, 1872. 

20. Laube und Bruder, Amm. d. bohm. Kreide. G. C. Laube und G. Bruder, Ammo- 

nites der bohmischen Kreide. Palaeontographica Bd. 33, 1887. 

21. Lisson, Amm. del Peru. C. I. Lisson, Contribucion al conocimiento sobre algunos 

Ammonites del Peru. 4o Congreso cientifico Latino-Americano, lo Panamer- 
icano, celebrado en Santiago de Chile. Lime, 1908. 

22. Lisson, Terr, recon. en el Peru. C. I. Lisson, Terrenes reconocidos hasta hoy 

en el Peru y sinopsis de su fauna y flora fosiles. Bol. de Minas, Ind. y Constr 
publ. por la Escuela de Ingenieros, ser. II, t. IV. Lima, 1912. 

23. Peron, Amm. du Cret. sup. de 1'Algerie. A Peron, Les ammonites du Cretace 

superieur de 1'Algerie. Mem. Soc. geol. France, Paleontologie, t. 6 et 7 
mem. no. 17. 1896-97. 

24. Pervinquiere, fit. geol. Tunisie. L. Pervinquiere, Etude geologique de la Tunisie 

182 University of Texas Bulletin 

Centrale. Theses presentees a la Faculte des Sciences de Paris p. obt. le 
grade de Docteur-es-Sciences Naturellea. Paris, 1903. 

25. Pervinquiere, Paleontologie Tunisienne. L. Pervinquiere, fitudes de Paleontologie 

Tunisienne. I Cephalopodes des Terrains Secondaires. Dir. Gen. des Travaux 
Publics, Carte geol. de la Tunisie. Paris, 1907. 

26. Petrascheck, Amm. d. sachs. Kreideform. W. Petrascheck, Die Ammoniten der 

sachsischen Kreideformation. Beitr. z. Pal. u. Geol. Oesterreich-Ungarns u. d 
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27. Petrascheck, Inoc. a. d. Kr. Bohmens. W. Petrascheck, Ueber Inoceramen aus 

der Kreide Bohmens und Sachsens. Jahrb. d. K. K. Geol. Keichsanstalt. Wien 
Bd. 53, 1903 (1904). 

28. Roemer, Kreidebild. v. Texas. F. Roemer, Die Kreidebildungen von Texas und 

ihre organischen Einschliisse. Bonn, 1852. 

29. Schlagintweit, Vracon u. Cenoman in Peru. 0. Schlagintweit, Die Fauna des 

Vracon und Cenoman in Peru. N. Jahrb. f. Min., Geol. u. Pal., Beilagebd. 
33, 1912. 

30. Sharpe, Secondary distr. of Portugal. D. Sharpe, On the Secondary District 

of Portugal which lies on the North of the Tagus. Quart. Jour. Geol. Soc 
London, Vol. VI, 1850. 

31. Sharpe, On Tylostoma. D. Sharpe, On Tylostoma, a proposed genus of Gaste- 

ropodous Mollusks. Quart. Jour. Geol. Soc. London, Vol. 4, 1849. 

32. Solger, Mungokreide. Fr. Solger, Die Fossilien der Mungokreide von Kamerun 

und ihre geologische Bedeutung, mit besonderer Beriicksichtigung der Am 
moniten. Beitrage zur Geologic von Kamerun herausgeg. v. E. Esch. Stutt- 
gart, 1904. 

33. Stanton, Colorado Form.- T. W. Stanton, The Colorado Formation and its in- 

vertebrate Fauna. U. S. Geol. Surv. Bull. No. 16, 1893. 

34. Stoliczka, Ceph. Cret. Rocks India. F. Stoliczka, The fossil cephalopoda of the 

Cretaceous Rocks of Southern India (Ammonitidae). Mem. of the Geolog- 
ical Surv. of India. Palaeontologia Indica, 1865. 

35. Thomas et Peron, Hauts-Plateaux de la Tunisie. Ph. Thomas et A. Peron 

Description des mollusques fossiles des Terrains Cretaces de la region sud 
des Hautes Plateaux de la Tunisie recueillis en 1885 et 1886. Exploration 
Scientifique de la Tunisie. Paris, 1889-90. 

36. White, Inv. foss. Nevada, Utah, etc. Ch. A. White, Report upon the inverte- 

brate fossils collected in portions of Nevada, Utah, Colorado, New Mexico, 
and Arizona, by parties of the expeditions of 1871, 1872, 1873 and 1874. 
Report upon Geogr. and Geol. Expl. and Surv. west of the 100th Meridian by 
Geo. A. Wheeler. Eng. Dept. U. S. Army, Part IV Palaeontology. Wash- 
ington, 1875. 

37. White, Brazil. Ch. A. White, Contributes a Paleontologia do Brazil. Archives 

do Museu Nacional do Rio de Jeneiro, Vol. VII, 1887. 

38. Woods, Cret. dep. Northern Nigeria. H. Woods, The palaeontology of the upper 

Cretaceous deposits of Northern Nigeria. The Geology and Geography of 
Northern Nigeria by J. D. Falconer. London and Bungay, 1911. 

39. Yabe, Cret. Ceph. Hokkaido II. H. Yabe, Cretaceous Cephalopoda from the 

Hokkaido. Part II. Jour, of the College of Science, Imp. Univ., Tokyo, 
1904, Vol. 20, art. 2. 

A New Ammonite Fauna of the Lower Turanian of Mexico 183 

40. Yabe, Strat, u. Pal. Hokkaido. H. Yabe, Zur Stratigraphie und Palaontologie 

der oberen Kreide von Hokkaido und Sachalin. Zeitschr. d. Deutsch. geol. 
Ges. Bd. 61, 1909. 

41. Zittel, Lib. Wiiste. K. A. Zittcl, Beitrage zur Geologie und Palaeontologie der 

Libyschen Wiiste und der angrenzenden Gebiete von Aegypten. I. Geolo- 
gischer Theil. Palaeontographica Bd. 30, I. 1883. 


The Cerro del Macho is a small hill in the eastern part of the Hacienda 
del Mohovano belonging to Mr. Frederick Ritter. The hacienda lies to the 
southeast of the station Carillo of the railway which connects Sierra Mo- 
jada, Coahuila with Escalon, Chihuahua (Mexican Central Railway) and 
part of its land belongs to the State of Chihuahua while the rest lies in the 
State of Coahuila. The Cerro del Macho belongs to this last region and 
lies near the boundary line of both states. 

Dr. E. Haarmann gave me the following geological cross-section of the 
fossiliferous locality, to which I add the stratigraphical explanation ob- 
tained as the result of the study of the fauna. 


Fig. 1 

Fossil bearing beds on the Cerro del Macho, Hacienda del Moh6vano, 

III. Gray hard limestones "1 

II. Gray-bluish marls J 

I. Yellow and red marls and argillaceous limestones Upper Cenoman- 

Lower Turonian. 

Three different petrographical horizons can be distinguished : the low 
est beds consist of yellow and red marls with argillaceous limestones con- 
taining numerous fossils, especially bivalves; this horizon which for the 
present we shall designate with the number I has a thickness of only two 

184 University of Texas Bulletin 

meters in this locality, but its base is covered. Above these marls lie gray- 
bluish marls with large cephalopods ; the thickness of this horizon which 
we designate as Number II, is 2.5 meters. On top of these marls we find 
gray limestones with numerous cephalopods, bivalves and gastropods ; the 
thickness of this horizon, which we call Number III, is about 5 to 6 meters, 
its upper limit being unknown. According to Dr. Haarmann the beds 
show a strike of N50-60E and a dip of approximately 10NW. 1 

The whole outcrop has thus only a thickness of about 10 meters, but 
nevertheless we find two different horizons, as will be shown in the 
following. Among the fossils collected in this locality I have been able to 
distinguish twenty-one different species which are distributed in the three 
horizons in the following manner : 
Horizon I. 

Metoecoceras aff. Whitei Hyatt 

Metoecoceras n. sp. 

Exogyra Haarmanni n. sp. 

Exogyra cfr. olisiponensis Sharpe 

Hemiaster sp. 
Horizon II. 

Mammites mohovanensis n. sp. 

Pseudaspidoceras aff. Footeanum Petrascheck 

Pseudaspidoceras aff. pedroanum White 

Vascoceras aff. Adonense Choffat 

Fagesia Haarmanni n. sp. 

Fagesia Pervinquieri n. sp. 
Horizon III. 

Vascoceras Angermanni n. sp. 

Vascoceras ex. aff. Gamai Choffat 

Vascoceras (?) sp. 

Vascoceras mohovanense n. sp. 

Neoptychites aff. xetriformis Pervinquiere 

Hoplitoides aff. mirabilis Pervinquiere 

Inoceramus labiatus Schlotheim 

Avicula Aguilerae n. sp. 

Trigonia sp. 

Crassatella sp. 

Tylostoma aff. ovatum Sharpe 

To show the stratigraphic importance of the different species we shall 
have to compare them with related forms. 

iAccording to a sketch of Dr. Angermann the strike of the beds i3 N-S and the 
dip 10 degrees W. 

A New Ammonite fauna of the Lower Turanian of Mexico 185 

Horizon I. 


Cenomanian Turonian 

Species from Cerro del Macho Related species 

Metoecoceras aff. Whitei Hyatt M. Whitei Hyatt ? T 

Metoecoceras n. sp. M. Geslianum Petrascheck + 

Exogyra Haarmanni n. sp. 

Exogyra cfr. olisiponensis Sharps Ex. olisiponensis Sharpe + + 

Hemiaster sp. 

The age of this horizon cannot be determined quite exactly. The fossils 
are few, the cephalopods among them indicate only that the horizon belongs 
either to the lower Turonian or the upper Cenomanian. Metoecoceras aff. 
Whitei is similar to forms found in the Colorado Formation of the United 
States, a division which up to now has not been subdivided stratigraphic- 
ally with the necessary exactness ; it probably represents in its larger part 
the Turonian, but may possibly contain some upper Cenomanian and a por- 
tion of Emscherian. The portion in which M. Whitei has been found be- 
longs to the lower part of the formation, which is either the lower Turonian 
or the upper Cenomanian. Our Metoecoceras n. sp. is very similar to M. 
Geslianum Petrascheck, 1 which occurs in the upper Cenomanian of Saxony, 
but we do not know exactly if our specimen has been found in this lowest 
horizon or in one a little higher. 

Interesting is the occurrence of an Exogyra certainly belonging to the 
group of Exogyra olisiponensis Sharpe. This species is found on the bor- 
der of the Mediterranean in the Cenomanian as well as in the Turonian, 
although the variety which is most similar to our specimen seems to be 
limited principally to the Cenomanian. Our Exogyra Haarmanni n. sp. is 
a new species and not very characteristic, therefore without any strati- 
graphic value. The Hemiaster found in the same bed can not be used for 
the determination of the age as it does not appear to be identical with any 
described species nor to be closely related to any known species which 
might indicate the age of these beds. 

The small number of fossils of this horizon does not allow an exact de- 
termination of its age. Taking into consideration the radical difference be- 
tween the character of this fauna and that of Horizon II, and the presence 
of a form of Metoecoceras very similar to the one of the upper Cenomanian 
of Saxony, I feel inclined to consider this horizon provisionally as upper 
Cenomanian until other and more characteristic fossils allow a more exact 
determination of the age. 

Much more numerous is the fauna of Cephalopods in Horizon II and 

iPetrascheck. Amm. d. sachs. Kreideform., 1.140 (10) pi. 7 (1) ; figs. 3-5. 

186 University of Texas Bulletin 

their forms are so characteristic that they easily allow the determination of 
the age of these beds. In the following table we shall compare them with 
related species of other countries. 

Horizon II. 


Species from Cerro del Macho Related species Lower Middle 

Mammites mohovanensis n. sp. M. nodosoides Schlotheim 

Pseudaspidoceras aff. Footeanum P. Footeanum Petrascheck + 

Pseudaspidoceras aff. pedroanum P. Footeanum Stoliczka + 

Vascoceras aff. adonense V. adonense Choffat + 

Fagesia Haarmanni n. sp. F. superstes Kossmat + 

Fagesia Pervinquieri n. sp. F. tevesthensis Peron + 

All the species of this horizon indicate that it belongs to the lower Tu- 
ronian or Salmurian. It s true that Choffat cites his Vascoceras adon- 
ense from the middle Turonian, but I believe that this middle Turonian of 
Portugal belongs in reality still to the Salmurian, i.e., the lower Turonian. 
The occurrence of forms belonging to the groups of Fagesia superstes, Fa- 
gesia tevesthensis, Mammites nodosoides, Inoceramus labiatus, etc., ap- 
pears to be quite decisive for the determination of the age of those beds. 
In our own case we have to consider that this horizon lies immediately 
above what we take to be upper Cenomanian ; there seems to be no reason 
to doubt that our Horizon II represents the very lowest Turonian. This 
idea is confirmed also by the fauna of Horizon III, which will be discussed 
farther on. 

Our Mammites mohovanensis is very nearly related to M. nodosoides 
Schlotheim. It differs principally in its broader cross section; still more 
similar to our species is Mammites conciliatus Stoliczka, which belongs to 
the same group, the main difference consisting in its more evolute form 
and some details of ornamentation. In these details our form is still more 
similar to a form determined by Fritsch as Mammites conciliatus which in 
reality occupies an intermediate position between our species and that of 

The species which we have called Pseudaspidoceras aff. Footeanum Pe- 
trascheck is much less related to the type of this group (P. Footeanum 
Stoliczka) than to the specimens from the lower Turonian of Saxony de- 
scribed by Petrascheck, on account of the more rounded and less subquad- 
rangular cross section, as well as the greater height of the whorl. This dif- 
ference may be explained in our section by its large size; comparing the 
different figured forms of P. Footeanum we see that the adult specimens 
tend to lose their quadrangular cross section. This group has been found 

A New Ammonite Fauna of the Lower Turanian of Mexico 187 

in the lower Turonian in many cases where an exact determination of the 
age of the beds has been possible. Varieties of this group have be.en de- 
scribed from India, from different parts of northern Africa, as Egypt 1 
and Tunis- ; from Portugal 3 , from Nigeria 4 , from Saxony"', and from Bra- 
zil." It is therefore a universally distributed form which characterizes the 
lower Turonian. 

To the same group of Pseudaspidoceras Footeanum belongs also the 
species called by me Pseudaspidoceras an*, pedroanum White. It is still 
nearer related to the Indian type than the former species, but differs by 
its less strong ribs and the smooth ventral part. In all its characters it is 
similar to the Ammonites pedroanus White and only differs in some de- 
tails of the ornamentation. The similarity is so great that I have not been 
able to separate the two forms specifically and have not united our speci- 
men with the Brazilian species only because this latter form is still imper- 
fectly known. ' . 

Our Vascoreras aff. adonense is certainly very similar to the Portuguese 
type from the Turonian, but differs by its suture and the form which is 
still more evolute. 

The form of greatest stratigraphic interest in our fauna is perhaps our 
Fagesia Haarmanni n. sp. It belongs to the group of Fagesia superstes 
Kossmat, but differs from the type as well as from all the other species of 
this genus by its more evolute form. The species belonging to this group 
are limited to the Turonian and especially to the lower part of it. The 
type was described from the Utatur group of India, 7 and a very typical 
form has also been found in Tunis 8 ; a nearly related species has been cited 
from the Turonian of Portugal. 

Fagesia Pervinqieri n. sp. is a very characteristic species and belongs to 
that group of Fagesia which loses its ribs in a rather juvenile state of 
growth ; the type of this group is Fagesia tevesthensis Peron. Our species 
differs from the type by its higher and less broad whorls. According to 
Pervinquiere Fagesia Rudra Stoliczka 10 belongs also to this group; this 

Zittel, Lib. Wuste, p. LXXIX (A. cfr. Footeanus) Eck, Turon in Acgypttn. p. 3^0 
(Acanthoceras cfr. Footeanum). 

2 Pervinquiere. Paleontologie Tunisienne, p. 314 (Mammites Salmuriensi*) . 
'Choffat, Especes nouv. ou peu conn., p. 66 (Acanthoceras cfr. Foolfanum', 
4 Woods, Cret. dep. Northern Nigeria, p. 283 (Mam-mites [Pseudaspidocerat] up.) 
^Petrascheck, Amm. d. sachs. Kreideform., p. 144 (Mammites f 
"White, Brazil, p. 212 (Ammonites pedroanus). 
'Kossmat, Sudindische Kreideform., p. 133, pi. 17, fig. 1. 
"Pervinquiere, Palecntologie Tunisienne, p. 322, pi. 20, fig. 1-3. 
Choffat, Especes nouv. ou peu conn., p. 69, pi. 10, fig. 4. 
'"Stoliczka, Ceph. Cret. Rocks India, p. 122, pi. 60. 

188 University of Texas Bulletin 

species which occurs in the Utatur group of India is similar to our species 
on account of the missing umbilical nodules in a stage of development 
which still shows the ribs on the ventral part; it differs, though, by its 
much broader and larger whorls. Another form which by Pervinquiere is 
considered as belonging to the same group is Ammonites Kotoi Yabe. 1 Per- 
vinquiere believes that this species is perhaps identical with Fagesia teves- 
thensis Peron, but it appears to me that we have here a different species 
although it is certainly related to the African form. According to Yabe 2 
it is not quite certain from which beds this form has been collected ; it oc- 
curs either in the Mammites beds or in the Scaphites beds. The age of 
Fagesia Rudra is not well known, although Kossmat presumes that this 
species belongs to the middle Utatur group. Fagesia tevesthensis charac- 
terizes the lower Turonian ; a very similar form exists in beds of the same 
age in France and another in the Turonian of Portugal. 

Still richer than the fauna of Horizon II is that of the upper limestones 
which we have distinguished as Horizon III. For their comparison with 
related species we shall again unite them in a table. 


Species from Cetro del Macho Related species Turonian Emscherian 

Vascocerat ' tigermanni n. sp. V. Kossmati Choffat + 

Vascocera*, ex aff. Gamai V. Gamai, Choffat + 

Vascoceras (?) sp. V. (?) arnesense Choffat + 

Vascoceras mohovanense n. sp. V. polymorphum Pervinquiere + 
Neoptychites aff. cephalotus N. cephalotus Courtiller + 

Neoptychites aff. xetriformis N. xetriformis Pervinquiere + 

Hoplitoides aff. mirabilis H. mirabilis Pervinquiere + 

Inoceramns labiatus Schlotheim /. labiatus Sch'otheim + 

Avicula Aguilerae n. sp. A. gravida Coquand + + 

Tylostoma aff. ovatum Sharpe T. ovatum Sharpe + (Cenomanian to 

upper Turonian 

Nearly all of the groups of ammonites cited in this list occur only in the 
lower Turonian, to which, according to my opinion, belong also the beds 
with Vascoceras of the so-called middle Turonian of Portugal. 

Vascoceras Angermanni n. sp. is very similar to V. Kossmati Choffat, 
but its form is still a little broader, there is no doubt that it belongs to the 
same group and this is until now only known in the Turonian of Portugal 
and the lower. Turonian of Egypt. 3 

The fossil which we have called Vascoceras ex. aff. Gamai Choffat is a 
juvenile form and not very well preserved which is very similar to the 

iYabe, Cret. Ceph. Hokkaido II, 26, pi. 6, figs. 3-4. 
2 Yabe, Strat. u. Pal. Hokkaido, p. 441. 
3 Eck, Turon in Tegypten, p. 381, 382. 

A New Ammonite Fauna of the Lower Turanian of Mexico 189 

small individuals figured by Choffat 1 in figures 3 and 4 of plate 7 and 
figure 2 of plate 10. Considering the size and state of preservation this 
specimen is not of great stratigraphic value. 

Vascoceras (?) sp. is a pretty large specimen which is very similar to 
Ammonites arnesensis Choffat. The generic determination is not quite 
certain as is also the case with A. arnesensis. Our specimen is a little 
twisted ; it does not have much importance for the determination of the 
age of the beds. 

Vascoceras mohovanense n. sp. is a specimen relatively small but very 
characteristic; it belongs certainly to the group of Vascoceras polymor- 
phum Pervinquiere of the lower Turonian of Tunis. It differs from the 
type by a missing intermediate row of nodules but in its general character 
and also in its suture is nearly related to the type. Pervinquiere considers 
Vascoceras subconciliatum Choffat from the Turonian of Portugal as a 
form of the same group but this species is different from ours on account 
of its general form and its suture. 

The species described by me as Neoptychites aff. cephalotus Courtiller is 
a juvenile specimen which resembles greatly the small individuals of the 
cited species, as has been demonstrated in the paleontological part of this 
paper. The group of Neoptychites cephalottts characterizes the lower Tu- 
ronian ; it occurs frequently in Algiers and Tunis, also in the neighborhood 
of Saumur, France. Similar and perhaps identical forms have been found 
in India (Neoptychites Telinga Stoliczka) 2 and in Kamerun (Neoptychites 
Telingaeformis Solger 3 ) ; the aee of the beds where these latter species 
have been found is not exactly known. 

The form which I compare with Neoptychites xetriformis Pervinouiere, 
is not very well preserved but resembles sufficiently the species from Tunis. 
Pervinquiere considers as a nearly related form Neoptychites crassus Sol- 
ger, 4 the age of this latter species is not determined with certainty. 

In the limestones of Horizon III we find frequently cephalopods which 
resemble very much the bicarinated Hoplitoides of Pervinauiere. The 
greater part of these specimens is entirely corroded but in one I have been 
able to prepare a portion of the interior whorl which clearly shows the ex- 
istence of the two lateral keels on the ventral portion ; one also notes the 
suture in part, certainly much destroyed but showing the same elements as 
in the bicarinated Hoplitoides. A large specimen has the external form of 

'Choffat, Especes nouv. cm peu conn. 

2 Stoliczka, Ceph. Cret. Rocks India, p. 125, pi. 62; Kossmat, Sudind. Kreideform., 
p. 71, pi. 7, fig. 1, pi. 17, fig. 13. 
'Solger, Mungokreide, p. 108. 
'Solger, Mungokreide, p. 119, pi. 3, fig. 5. 

190 University of Texas Bulletin 

Hoplitoides mirabilis but is a little less involute. This group is of some in- 
terest in so far as having been found only in the lower and upper Turon- 
ian. The types of Hoplitoides mirabilis 1 and H. Munieri 2 occur in Tunis 
mainly in the lower Turonian, H. Munieri also in the upper Turonian. A 
similar species has been found also in the Turonian of Egypt. 3 

In the same Horizon III, Dr. E. Haarmann also collected four specimens 
of Inoceramus of which three are typical individuals of Inoceramus labia- 
tus Schlotheim. According to an observation made by Jose G. Aguilera, 
this fossil occurs in great numbers in beds north of the station of Carillo 
which apparently overlie limestones identical with those described here. 

In Horizon III occurs very frequently Avicula Aguilerae n. sp. This 
species is very similar to Avicula- gravida Coquand which occurs in north- 
ern Africa in the Turonian as well as in the lower Senonian or Emscherian. 
The form and size of this Avicula are so similar to those of ours that this 
find in Mexico has a certain stratigraphic interest. 

In the material of Horizon III we find a great number of other bivalves, 
but all in the state of internal molds ; a specific determination is entirely 
impossible. The most frequent form probably belongs to Tylostoma or 
some subgenus of Natica; the greater part of the material is badly pre- 
served, but some specimens are a little more complete, although preserved 
as internal molds, and resemble strongly Tylostoma ovatum Sharpe which 
in Portugal occurs in beds from the Cenomanian to the upper Turonian. 

From the character of the fauna of Horizon III we have to conclude that 
these beds still belong to the lower Turonian. This appears rather proba- 
ble from the circumstance that Horizon II is extremely thin and is well 
confirmed especially by the cephalopod fauna. Interesting is the occur- 
rence of Inoceramus labiatus Scholtheim. This fossil is extremely common 
in Mexico and generally is found in great numbers in calcareous shales 
and shaly limestones. The question now is, what relation exists between 
those beds and those of Cerro del Macho? In the described locality the 
shales, etc., do not exist, but according to the identification of J. G. Aguil- 
era these are found north of the station of Carillo where they apparently 
overlie limestones similar to those of the Cerro del Macho. If we accept 
this explanation, our beds at Cerro del Macho have to be considered as the 
lowest part of the Turonian, while the shales with Inoceramus labiatus 
would be a little younger and perhaps represent the lower as well as the 
upper Turonian. We have no data with which to solve this problem, as up 
to now the beds with Inoceramus labiatus have not been found in contact 

1 Pervinquiere, Paleontologie Tunisienne, p. 218, pi. 10, fig. 3. 
2 Idem, ibid., p. 217, pi. 10, figs. 1, 2. 
3 Eck, Turon in Aegypten, p. 380, 386. 

A New Ammonite Fauna of the Lower Turanian of Mexico 191 

with the cephalopod beds described here ; neither have those beds with Ino- 
ceramus labiatus been found in immediate contact with fossiliferous beds 
of the Emscherian. Only in one place, Opal, Zacatecas, I have found beds 
with Inoceramus labiatus (rare) and /. hercymicus (very frequent) in 
contact with sandstones containing an Inoceramus nearly related to Inoce- 
ramus cycloides, but the cross section of this locality is too incomplete and 
the fauna too poor for a decision of this rather important problem. 

The locality of Cerro del Macho is stratigraphically important in so far 
as it gives us some data for the limitation of the upper Cenomanian and 
the lower Turonian. In a former work we have been able to subdivide the 
Cenomanian of Cerro de Muleros near Ciudad Juarez, but we have not been 
able to find fossils in the sandstones between the beds with Inoceramus 
labiatus and the marls with Hemiaster'Calvini; thus it was impossible to 
decide if those sandstones belonged to the Cenomanian or the Turonian. 
In the present case we have very fossiliferous beds very near the limit be- 
tween the Cenomanian and the Turonian. The fossils of the Cenomanian 
are very different from those found up to the present in Cenomanian rocks 
of Mexico. Of especial importance is the occurrence of Metoecoceras. 
The Turonian ammonite fauna is also entirely new for Mexico, the few 
ammonites so far found in the beds with Inoceramus labiatus belonging to 
entirely different groups. 

Haarmann has distinguished two horizons, II and III, but these do not 
appear to be more than local subdivisions notwithstanding the circum- 
stance that the fauna of the two beds seem to be rather different. We must 
not give too much importance to this circumstance, as the collections so far 
made are still rather small and the aspect of the fauna may change alto- 
gether with larger collections made. As far as we can see, the lower bed 
contains principally cephalopods while in the upper one bivalves and gas- 
tropods predominate. 

With respect to the conditions of life in this locality we may say with 
some certainty that at the end of the CeYiomanian in the Cerro del Macho 
region as well as in others of northern Mexico, especially in the State of 
Chihuahua, there existed a littoral facies or at least a very shallow sea; 
this is indicated by the great quantity of Ostreidae which nearly form beds 
or which have been carried away from neighboring beds. At the begin- 
ning of the Turonian age the sea seems to have deepened a little, the pre- 
dominance of the ammonites and the absence of littoral bivalves indicating 
a less shallow sea. It is probable that during the time of the deposition of 
the upper part of the Salmurian the sea again became a little shallower; 
this is indicated by the predominance of Lamellibranchia and Gastropoda 
with thick shells, but the facies is not quite as much a littoral one as in 


University of Texas Bulletin 

Cerro del Muleros near Ciudad Juarez at the same time, where the corre- 
sponding beds consist entirely of sandstones. 

According to the observations of Haarmann and our palaeontological 
studies the stratigraphical cross section of the Cerro del Macho presents 
the following features : 

5-6 m. of gray limestones with: 
Vascoceras Angermanni n. sp., V. ex aff. Gamai Choffat, 
Vase, sp., V. mohovanense n. sp., Neoptycliites aff. cepha- 
lotus Courtiller, N. aff. xetriformis Pervinquiere, Hopli- 
toides aff. mirabilis Pervinquiere, Inoceramus labiatt 1 ? 
Schlotheim, Avicula Aguilerae n. sp., Tngonia sp., Cras- 
satella sp., Tylostoma aff. ovatum Sharpe, (Lamellibran- 
chia and Gastropoda extremely frr-quentj^ 

Hor. Ill 



2.5 m. of gray-bluish marls with: 
Mammites mohovanensis n. sp., Pseudaspidoceras arf 
Footeanum Petrascheck, Ps. aff. pedroanum White, Vasco- 
ceras aff. adonense Choffat, Fagesia Haarmanni n. sp 
F. Perviniquieri n. sp. 

Hor. II 

2 m. yellow and reddish marls and limestones with: 
Metoecoceras aff. Whitei Hyatt, Meto?.co-;eras nov. sp., 
Exogyra Haarmanvi n. sp., Ex. cfr. disiponensis Sharpe 
Hemiaster sp. (Lamellibranchia predominate). 

Hor. I 


If really the beds with Inoceramus labiatus lie immediately on top of the 
cephalopod beds, as the observations of J. G. Aguilera seem to indicate, 
another deepening of the sea may have followed and the general rising 
of the bottom of the ocean did not begin before the age of the lower Se- 



The fauna of the upper Cenomanian of Cerro del Macho is too small 
to be compared with others ; the most important fossil, Metoecoceras n. sp. 
belongs to a group which has been found in the upper Cenomanian. Of 
certain interest is the occurrence of Exogyra cfr. olisiponensis Sharpe be- 
cause it indicates a faunistic similarity with the development of the Ceno- 
manian along the border of the Mediterranean, a circumstance which to a 
certain degree can be noted also in the fauna of other Cenomanian beds 
of Mexico. 

A New Ammonite Fauna of the Lower Turanian of Mexico 193 


The fossils of the lower Turonian or Salmurian of the Cerro del Macho 
present a much better material for faunistic comparisons. Already while 
comparing our species with related ones from other regions we have seen 
that similar forms are found mainly around the Mediterranean, inclusive 
of Portugal. Comparing the faunas of the Salmurian in the above men- 
tioned region, we find that all of them contain certain elements which 
either do not exist in most other regions or which occur only very rarely 
there. We shall see later on that this special fauna is not restricted to 
the Mediterranean but extends also to other parts of Africa and that 
certain elements belonging to it occur also in Asia and America. This 
indicates a large extension of the same horizon, but 1 at the present time 
it is impossible to say if this distribution coincides with that of the same 
paleontological facies. But before we enter into such a discussion we must 
compare our fauna with the isochronous faunas of the Mediterranean and 
other parts of the earth in a somewhat more detailed manner. 

Portugal: We begin with the region of Portugal. According to Choffat 1 
we find in the lower part of the Turonian (beds with Ostrea columba 
major) the following cephalopods: 

Puzosia cfr. planulata Sowerby 

Vascoceras Mundae Choffat 

Vascoceras Gamai Choffat 

Pseudaspidoceras cfr. Footeanum Stoliczka 

Neolobites sp. nov. 
In his middle Turonian we find the following species: 

Vascoceras Gamai Choffat 

Vascoceras Gamai Choffat var. triangularis Choffat 

Vascoceras Mundae Choffat 

Vascoceras amieirense Choffat 

Vascoceras silvanense Choffat 

Vascoceras adonense Choffat 

Vascoceras Grossouvrei Choffat 

Vascoceras Barcoicense Choffat 

Vascoceras Douvillei Choffat 

Vascoceras subconciliatum Choffat 

Vascoceras harttiforme Choffat 

Vascoceras Kossmati Choffat 

Vascoceras ( ?) arnesense Choffat 

iChoffat, Syst. cret. Portugal II. p. 162, 170, 173. 
Choffat, Especes nouv. ou peu conn., p. 44, 47. 

194 University of Texas Bulletin 

Mammites pseudonodosoides Choffat 
Pseudaspidoceras cfr. Footeanum Stoliczka 
Fagesia aff. superstes Kossmat 
Fagesia aff. tevesthensis Peron 
Puzosia cfr. Gaudama Forbes 
Puzosia sp. 

Pachydiscus peramplus var. beyrense Choffat 
Pseudotissotia Barjonai Choffat 
Ammonites cfr. Pachydiscus Rollandi Peron 
Ammonites sp. ind. 

From the upper Turonian the author cites: 
Vascoceras Gamai Choffat 
Schloenbachia ? 

Algeria: The Salmurian in northern Africa, especially in Algeria, Tunis 
and Egypt is very well developed. Still, in the year of 1904, Solger 1 
could not cite from Algeria more than the following species of cephalopods : 
According to Peron : 

Acanthoceras deverioide Grossouvre 

Sphenodiscus Requiem d'Orbigny (Hoplitoides ingens according to 


Pachydiscus peramplus Mantell and other species of the same genus 
Neoptychites Telinga Stoliczka (N. cephalotus according to Per- 

Puzosia Austeni Sharpe 
According to Coquand: 

Amm. Fleuriausi d'Orbigny 

Amm. papalis d'Orbigny 

Hetet -ammonites ammoniticeras Coquand (Hemitissotia Morreni 

Coquand according to Pervinquiere) 
Peron cites further the following species: 2 

Mammites ? tevesthensis Peron (=Fagesia tevesthensis according 

to Pervinquiere) 

Pachydiscus Durandi Thomas et Peron (^Vascoceras Durandi ac- 
cording to Pervinquiere) 
Pachydiscus Rollandi Peron (=Thomasites Rollandi according to 


Tunis: In the present time we owe to the painstaking investigations 
of L. Pervinquiere a much more complete knowledge of the fauna of the 

iSolger, Mungokreide p. 203. 

2 Peron, Amm. du Cret. sup. de 1'Algerie. 

A New Ammonite Fauna of the Lower Turanian of Mexico 195 

Salmurian in northern Africa, especially of Tunis. Pervinquiere cites 
and describes the following cephalopods: 

Puzosia Austeni ? Sharpe 

Pachydiscus peramplus Mantell 

Hoplitoides Munieri Pervinquiere 

Hoplitoides mirabilis Pervinquiere 

Prionotropis Neptuni Geinitz 

Acanthoceras Douvillei Pervinquiere 

Mammites nodosoides Schlotheim 

Pseudaspidoceras salmuriense Courtiller 

Pseudaspidoceras armatum Pervinquiere 

Fagesia superstes Kossmat 

Fagesia tevesthensis Peron 

Fagesia Peroni Pervinquiere 

Fagesia Fleuryi Pervinquiere 

Vascoceras Durandi Thomas et Peron 

Vascoceras cfr. barcoicense Choffat 

Vascoceras polymorphum Pervinquiere 

Thomasites Rollandi Peron 

Thomasites Meslei Pervinquiere 

Thomasites Jordani Pervinquiere 

Pseudotissotia segnis Solger 

Pseudotissotia Pavillieri Pervinquiere 

Pseudotissotia Luciae Pervinquiere 

Pseudotissotia Massipiana Pervinquiere 

Neoptychites cephalotus Courtiller 

Neoptychites xetriformis Pervinquiere 

Neoptychites Courguechoni Pervinquiere 

Egypt: Until a very few years ago our knowledge of Turonian faunas 
of Egypt was rather fragmentary, but in 1911 Eck published a prelim- 
inary study 1 of the collections made by Schweinfurth which contain faunas 
of the Cenomanian, Turonian and Senonian. From the lower Turonian 
Eck cites the following cephalopods : 

Neolobites Schweinfurthi Eck 

Fagesia bomba Eck 

Fagesia cfr. tevesthenensis Peron 

Vascoceras cfr. amieirense Choffat 

Vascoceras Kossmati Choffat 

a Eck, Turon in Aegypten. (On account of the war I have not been able to obtain 
the later work of the author.) 

196 University of Texas Bulletin 

Vascoceras Durandi Thomas et Peron 

Vascoceras barcoicense Choffat 

Pseudotissotia segnis Solger 

Pseudaspidoceras cfr. Footeanum Stoliczka 

Hoplitoides sp. (?) 

Hoplitoides cfr. mirabilis Pervinquiere ( ?) 

Southern Sahara: In Africa there are other localities where fossils 
indicating- the existence of the Salmurian in a facies similar to that of 
Portugal, Tunis, Egypt, etc., have been found. Chudeau 1 describes some 
cephalopods from Damergou, a region which lies nearly exactly where 
Longitude 9E Greenwich crosses Latitude 15N. This author cites from 
that part: 

Vascoceras Cauvini Chudeau 

Acanthoceras Gadeni Chudeau 

According to the author Vascoceras Caudini is similar to V. Durandi 
Thomas et Peron. 

Nigeria? Woods 2 describes several cephalopods from northern Nigeria 
which seem to belong to Turonian forms. The species described are the 
following : 

Vascoceras Nigeriense Woods (similar to V. Durandi Thomas et 

Vascoceras Gongilense Woods (similar to V. subconciliatum Chof- 

Pseudaspidoceras sp. (similar to Ps. Footeanum Stoliczka) 

Hoplitoides Nigeriensis Woods (similar to H. Munieri Pervinquiere) 

Kamerun: One can not doubt that the above cited fauna represents the 
Turonian and probably the Salmurian; therefore it is rather astonishing 
that a similar fauna has not been discovered in Kamerun, where only the 
Neoptychites of the Mungo remind us of Salmurian forms. Solger sup- 
poses that the Turonian exists in that region, but Guillemain and Harbort 3 
maintain that the beds in all their extension belong to the Emscherian. 

From what we have seen in the foregoing description we conceive the 
idea that in northern and central Africa and in Portugal exists a facies 
of special features representing the Salmurian. This facies is distin- 
guished by the frequence of the genera: Vascoceras, Fagesia, Neopty- 
chites, Pseudaspidoceras, and in second place Pseudotissotia, Thomasites 
and Hoplitoides. 

Chudeau, Ammonites du Damergou, p. 66. 

2 Woods, Cret. dep. northern Nigeria, pp. 281-286. 

3 Guillemain und Harbort. Profil der Kreidesch. a. Mungo, p. 431. 

A New Ammonite Fauna of the Lower Turanian of Mexico 197 

Syria and Palestine: Of this characteristic fauna nothing seems to be 
known in other parts of the Mediterranean. In Syria and Palestine, 
Turonian beds are scarcely known. Notling cites from there a cephalopod 
similar to Prionotropis Woolgari, and Diener cites a Mammites nodosoides. 
This does not prove that .the Salmurian in its north African facies does not 
exist there, because only a few years ago we did not know any more about 
the Turonian of Egypt, until Eck published his first lists of cephalopods. 

Southern France: It seems that on the European border of the Med- 
iterranean the north African facies of the Salmurian with its character- 
istic fauna of cephalopods is yet unknown. In France the same horizon 
has quite a different fauna. In Provence there are, according to Gros- 
souvre, 1 beds with: Mammites nodosoides, M. conciliatus and Pseudo- 
tissotia Douvillei, but at least the first two of these species are nearly 
universally distributed types. Pervinquiere adds to this list Fagesia 
Boucheroni Coquand. In Aquitania the following cephalopods have been 
found : Pseudaspidoceras salmuriense, Fagesia superstes ?, Fagesia Bou- 
cheroni Coquand, Fagesia tevesthensis, and Neoptychites cephalotus. 
Thus this fauna contains quite a good number of the Salmurian fauna of 
the Mediterranean, although in the case of Fagesia and Neoptychites it 
seems that only very rare specimens have b.een found. 

Saxony and Bohemia: The fauna of tli- Salmurian in Saxony and 
Bohemia contains a still smaller number of elements which might belong 
to the Mediterranean facies. Fritsch- describes from there as Mammites 
conciliatus Stoliczka a form which certainly belongs to this group, although 
as Kossmat already has noted, the species is different. The same author 
cites Acanthoceras Neptuni. Laube and Bruder 3 figure Mammites nodo- 
soides and other species of this genus, as well as Puzosia Austeni. Petra- 
scheck* cites Mammites Footeanus Stoliczka, Mammites cfr. crassitesta 
Stoliczka, Barroisiceras ( ?) Fleuriausianum d'Orbigny, Acanthoceras cfr. 
Choffati Kossmat; all forms of groups which in part occur around the 
Mediterranean and in part in India. 

Northern Europe: The faunas of the Salmurian of northern France 
and nothern Germany show much less similarity with the Mediterranean 
facies. They contain only ammonites belonging to groups of a universal 
distribution, like Mammites nodosoides, Barroisiceras (?) Fleuriausianum, 
Acanthoceras Neptuni, Pachydiscus peramplus, Puzosia Austeni, etc. Of 
course, we have to take into consideration that neither in northern Ger- 

'Grossouvre, Craie Superteure, Stratigr., p. 507. 
2 Fritsch, Ceph. bohm. Kreideform., p. 35. 
3 Laube und Bruder, Amm. d. bohm. Kreide, p. 229. 
Petrascheck, Amm. d. sachs. Kreideform., p. 155. 

198 University of Texas Bulletin 

many nor in Bohemia is there a modern stratigraphic-paleontological work 
on the Turonian fauna. 

Less still do we know about England, from which Solgar could cite 
only a very few species as probably of Turonian age. 

From the foregoing we see that the more we advance toward the north, 
the more the elements belonging to the Mediterranean facies of the Sal- 
murian diminish. 

India: Certain faunal relations exist between the Salmurian of India 
and that of the Mediterranean. In India the group of Mammites nodo- 
soides is represented by two species, Mammites conciliatus Stoliczka and 
M. crassitesta Stoliczka; the group Pseudaspidoceras by one, Ps. Footea- 
num Stoliczka. The genus Fagesia is represented by two species, Fagesia 
superstes Kossmat, and F. Rudra Stoliczka. In the same manner we find 
Neoptychites represented by two species: Neuptychites Telinga Stoliczka 
(=cephalotus Courtiller according to Pervinquiere) and N. xetra Stoliczka. 

Japan: In Japan there is probably also Turonian with elements of the 
Mediterranean facies. Yabe cites the occurrence of beds with Mammites. 
In these he found a Mammites of the group of M. nodosoides Schlotheim. 1 
The same author describes a Fagesia Kotoi which occurs either in the same 
beds or in those with Scaphites, which are a little younger. 

Australia: It seems that in Australia the Turonian has not yet been 
found; at least the fossils found in the Desert Sandstone, considered by 
Jack and Etheridge as the representative of the upper Cretaceous, 2 do not 
allow such a conclusion. 

Brazil: In South America only very few localities have been discov- 
ered where fossils of the Salmurian have been found. Some species were 
described from Brazil by White but without any indication of their age. 
Several authors have already noted that the Salmurian must exist there, 
but it seems nearly impossible to separate the Salmurian fossils from 
those of the other Cretaceous horizons. Pervinquiere notes the similarity 
between Vascoceras Durandi and Ammonites Harttii Hyatt, 3 while Choffat 
who had before that time called attention to the similarity between that 
species and his Vascoceras harttiforme Kossmat believes that A. Harttii 
might be a Fagesia, but the suture published by Hyatt 4 shows that the 
species belongs to Vascoceras. 

Kossmat has also indicated the similarity between Ammonites pedroanus 

iYabe, Strat. u. Pal. Hokkaido, p. 441. 
-Jack and Etheridge, Queensland, p. 557 et seq. 

3 White, Brazil, p. 226, pi. 19, figs. 1, 2; pi. 20, fig. 3 (erroneously called A. Pedroanus 
in the explanation of the plate and in the text). 
*Hyatt, Pseudocer., pi. 14, fig. 16. 

A New Ammonite Fauna of the Lower Turanian of Mexico 199 

White 1 and Pseudaspidoceras Footeanum Stoliczka. This species is found 
at the same locality (Bom Jesus, Larangeiras, Provincia de Sergipe) where 
Vascoceras Harttii occurs. It is therefore probably safe to say that the 
Salmurian exists in that region in a facies similar to that of northern 

Pervinquiere finally has noted that his Vascoceras polymorphism is very 
similar to Ammonites offarcinatus White, 2 a species found at Trapiche 
das Pedras Velho, Porto dos Barcos and Bom Jardin in the Province of 
Sergipe. It seems to me probable that this type belongs to the multi- 
tuberculated Vascoceras. 

Peru: Species from the Salmurian have also been found in Peru. Lis- 
son 3 described and figured in 1908 two specimens of Vascoceras which he 
identifies with Vase, amieirense Choffat. There can be no doubt that this 
form is a real Vascoceras very similar to Vase, amieirense, although the 
Peruvian form is a little more involute and the cross-section different. 
Later on Lisson 4 cites from Cuesta de Huanambra, in the province of Caja- 
marca, a Mammites nodosoides var. Afra Pervinquiere, but notes that the 
fossil seems to occur in the lower Senonian (Emscherian). From the 
same locality he cites Hoplitoides ingens v. Koenen ; this makes the deter- 
mination of the first species doubtful or indicates that both the Salmurian 
and the Emscherian exist in this locality. This latter opinion is con- 
firmed by a geological cross-section published by Schlagintweit, 5 whose 
locality "Cuesta de Huanyanba," is probably identical with the "Cuesta de 
Huanambra" of Lisson, as both indicate that the place lies to the west of 
Celendin. Schlagintweit gives the following cross-section: 

6. Senonian beds. 

5. Few meters of marly limestones of yellow color with Mammites 
nodosoides Schlotheim. Turonian. 

4. About 15 m. sandy dolomitic limestone. 

3. Few meters of yellow marls of the Cenomanian with Exogyra 
columba Lamarck. 

2. 100-150 meters of light-colored limestone. Vraconian. 

1. Aptian-Gault with fossils. 

United States: In the rest of America no fauna similar to the Medit- 
erranean facies of the Salmurian appears to have been discovered. In the 
western United States the Turonian is represented by the Eagleford shales, 

'White, Brazil, p. 213, pi. 22, figs. 1, 2 (won pi. 20, fig. 3). 
'White, Brazil, p. 219, pi. 23, figs. 3, 4. 
s Lisson, Amm. del Peru, p. 9, 9a, 9b. 
4 Lisson, Terr, recon. en el Peru, II, p. 1. 
5 Schlagintweit, Vravon u. Cenoman i. Peru, p. 57. 

200 University of Texas Bulletin 

similar to the beds of Mexico, with Inoceramus labiatus ; and in the central 
United States by the Benton and the Colorado formation. This latter 
probably contains also the Emscherian. The cephalopods collected in these 
beds are entirely different from those of the Mediterranean Salmurian 
and seem to occur in slightly younger beds. Possibly the Salmurian may 
yet be found in Texas, as there is only a short distance between this state 
and our locality. 

From the foregoing we reach the conclusion that our fauna of Cerro 
del Macho has very near relations with the African and Portuguese facies 
of the Salmurian and that a similar fauna probably exists in South Amer- 
ica on the Pacific coast (Peru) as well as on the Atlantic border (Brazil). 
In South America, especially in Peru, the similarity with the faunas of 
north Africa appears to begin even in the Cenomanian (Schlagintweit) 
and to persist still in the Senonian (Lisson), while in Mexico we can 
not say the same, although in the Cenomanian as well as in the Senonian 
there exist certain elements which remind us of forms from north Africa. 
We certainly have to take into consideration that the fauna of the Ceno- 
manian of Mexico is still very little known, only the faunas of Cerro del 
Muleros and of the Vraconian of Camacho, Zacatecas, having been studied 
in detail; and this latter fauna resembles entirely that of Europe. The 
few fossils contained in the probably Cenomanian beds of Cerro del Macho 
seem to indicate in a certain degree that the upper Cenomanian of this 
region has a fauna similar to that of north Africa; but this problem 
can only be solved in the future when larger collections have been made. 

The Salmurian faunas of the African-Portuguese region as well as those 
of Cerro del Macho have some, although not very near, relations with the 
Salmurian of India and Japan, the connecting elements consisting of a few 
groups of Mammites, Pseudaspidoceras, Fagesia and Neoptychites; and 
we might even say that our facies is as much related to that of India and 
Japan, as it is to that of France and Saxony-Bohemia. 

I do not pretend that these results are to be considered as definite, 
because the Salmurian in general is yet very little studied, not only in 
far away countries like India and Japan but also in a great part of Europe. 


Hyatt 1 proposed the name of Metoecoceras 2 for the forms belonging to 
the group of Ammonites Swallovi Shumard and united in the genus the 

iHyatt, Pseudocer., p. 116. 

2 I accept the proposal of Pervinquiere to change the original name Metmcoccras 
into Metoecoceras. 

A New Ammonite Fauna of the Lower Turanian of Mexico 201 

following species : M. Swallowi Shumard, M . gibbosum Hyatt, M. Whitei 
Hyatt, M. acceleratum Hyatt, and M. Kanabense Hyatt (figured but not de- 
scribed). These are forms similar to Acanthoceras in one direction and to 
Pulchellia in the other ; they are always involute, with relatively flat flanks, 
a nearly rectangular or lanceolate cross section, much higher than broad. 
The ornamentation consists of straight or slightly flexous ribs which begin 
at the umbilical border without forming real nodules in that region, al- 
though in some cases they show slight thickening in that place. The ribs 
continue on the flanks, showing near the ventral border a thickening or 
very little pronounced nodule, and on the ventral shoulder a very sharp nod- 
ule which is somewhat longitudinally prolonged and very near the above 
mentioned thickening. Between the main ribs other secondary ribs are 
intercalated which begin above the umbilical border in different heights ; 
the main ribs are often bifurcated. Between the two rows of nodules on 
the ventral shoulders there is a flattened zone, smooth in some cases while 
in others the very low ribs cross this zone. The nodules of the two ventral 
shoulders frequently form a kind of undulated or interrupted keels. 

The suture of small individuals resembles that of Heinzia and Pulchellia, 
while that of larger specimens is similar to the suture of certain groups of 
Acanthoceras (Mantelliceras) and Acompsoceras. Characteristic is the ex- 
ternal saddle divided by a secondary rather deep lobe ; the first lateral lobe 
is broad and not very deep, the first lateral saddle is narrow but in general 
higher than the external saddle; the second lateral lobe is narrow and 
short, showing scarcely half of the depth of the first one. The second lat- 
eral saddle is similar to the first one but much lower; there are always 
three or four auxiliary saddles or even more in very large specimens. All 
the saddles are very little ramified, the auxiliary ones often entirely whole. 
The first lateral lobe seems to be always bifid. 

Very characteristic also is the manner of involution in this genus. While 
the internal whorls are completely involute, the external whorl covering 
the greater part of the inner one, we see that the larger whorls and the 
animal chamber show a much wider curve and cover a much larger part of 
the next smaller whorl. 

The species belonging to this group are so characteristic that one has to 
consider them as an independent genus or subgenus. Hyatt considers this 
group as a special family, giving it a position between the Heinzidae and 
the Mantelliceratidae. 

To the species united by Hyatt in the genus Metoecoceras we probably 
have to add some European forms. One of these is Pulchellia Gesliana 
Petrascheck 1 from the upper Cenomanian of Saxony. Petrascheck con- 

1 Petrascheck, Amm. d. sachs. Kreideform., p. 140, pi. 7, figs. 3-5. 

202 University of Texas Bulletin 

siders this species as a Pulchellia and it certainly has the greatest sim- 
ilarity with this genus if we do not take into account Metoecoceras. . Com- 
paring the figures of Petrascheck with those of the American Metoeco- 
ceras we note a surprising similarity ; for example, between figure 4 of Pe- 
trascheck and figure 2 of Stanton, 1 and between, figure 3 of Petrascheck 
and figure 10 of plate 15 of Hyatt. 2 

The suture of the specimens from Saxony is imperfectly known, but the 
elements which can be recognized in figure 4 of plate 7 and figure 5 of the 
text (p. 141) of Petrascheck, coincide very well with those of Metoecoceras. 

Petrascheck identifies his specimens with Ammonites Geslianus d'Or- 
bigny,* but Sayn points out that the figure of d'Orbigny differs very much 
from the figures of Petrascheck. It is possible that Ammonites Geslianus 
d'Orbigny belongs also to Metoecoceras but this can not be decided as long 
as the suture is entirely unknown. The specimen figured by Gueranger" 
under the name of A. Geslianus is so badly preserved that no details can be 
recognized. What Geinitz 5 figures as A. Geslianus d'Orbigny seems to 
differ considerably from the type and belongs perhaps to Stoliczkaia. Pe- 
trascheck accepts the determination of Geinitz but does not figure any 
specimen which shows the transition between the smooth ventral part and 
the form in which the ribs pass the venter without interruption. 

Kossmat 6 has noted the external similarity between Acanthoceras vici- 
nale Stoliczka 7 and "Buchiceras" Swallovi Shumard, indicating at the same 
time the difference in the suture which is much more complicated, especially 
in the auxiliary saddles of the Indian species. 

Still more similar to M. Swallovi is a cephalopod from Madagascar de- 
scribed by Boule, Lemoine and Thevenin 8 under the name of Acanthoceras 
(Prionotropis) subvicinale. The suture of these specimens coincides per- 
fectly with that of Metoecoceras, as has already been observed by the au- 
thors, but it also has a great similarity with Pulchellia. The specimens are 
very small and show an ornamentation very similar to that of Metoecoce- 

^tanton, Colorado Form., p. 168, pi. 38 (Buchiceras Swallovi White; according to 
Hyatt, this is a new species, M. Whitei, Hyatt). 

2 Hyatt, Pseudocer. 

3 D'Orbigny, Pal. fran c.,terr. cret., ceph. p. 325, pi. 97, figs. 1-2 (under the name of 
Am. catillus Sow.; this determination was corrected by d'Orbigny in Prodrfime II, 
p. 146). 

4 Gueranger, Album Paleontol., pi. 5, fig. 2. 

5 Geinitz, Elbthalgebirge I, p. 280, pi. 62, fig. 3. 

6 Kossmat, Siidind. Kreideform., p. 201 (105). 

'Stoliczka, Ceph. Cret. Rocks India, p. 84, pi. 44. Kossmat, Siidind. Kreideform.. 
p. 200 (104), pi. 25 (11), fig. 2. 

"Boule, Lemoine et Thevenin, Diego-Suarez, p. 31, pi. 8, fig. 5; fig. 16 of the text. 

A New Ammonite Fauna of the Lower Turonian of Mexico 203 

ras; they differ principally by the presence of a median row of scarcely 
perceptible, very small tubercles on the ventral part. Unfortunately the 
specimens are all very small, therefore we can not know if this row of tu- 
bercles becomes stronger in larger specimens, or if it disappears com- 
pletely, or if it persists in larger individuals in the same manner as in 
juvenile specimens. Hyatt does not mention the existence of a median 
row of tubercles in juvenile specimens of Metoecoceras. Acanthoceras 
subvicinale occurs in the Cenomanian of Diego-Suarez. 

Thus we see that in Europe as well as in India and Madagascar there 
seem to exist forms which resemble the Metoecoceras of America. Prob- 
ably we have to include in this genus at least Pulchellia Gesliana Petras- 
check and perhaps also Ammonites Geslianus d'Orbigny. Very similar is 
also Acanthoceras subvicinale Boule, Lemoine et Thevenin, especially on 
account of the suture, while Acanthoceras vicinale Stoliczka, although 
showing a very similar ornamentation, differs by its more complicated 
suture. But we should note that the suture changes considerably in the 
different Metoeceras of America, that of M. Whitei being much more com- 
plicated than that of M. Swallovi (in the limitation of Hyatt). At pres- 
ent we can not decide how many forms should/ be included in the genus 
Metoecoceras, but can only indicate that this genus is probably represented 
in the Cenomanian of Europe and perhaps of Madagascar, and that similar 
forms but with a much more complicated suture, are found in the Ceno- 
manian and Turonian of India. 


PL 12 figures 4, 7 

1876: Buchiceras svallovi White, Inv. foss. Nevada, Utah, etc., p. 202, pi. 20. 
1893: Buchiecras svallovi Stanton, Colorado Form., p. 168, pi. 37, fig. 1 (?pl. 38, 

figs. 1-3). 
1903: Meloicoceras Whitei Hyatt, Pseudocer., p. 122, pi. 13, figs. 3-5, pi. 14, figs. 1-10, 

fig. 15. 

In the lower bed of Cerro del Macho occur two fragments of cephalopods 
which greatly resemble the group of Metoecoceras Whitei: they are espec- 
ially similar to specimens figured by Hyatt. Our individuals show the fol- 
lowing features : 

Shell discoidal, very involute, with whorls of nearly rectangular cross 
section, much higher than broad. The flanks are very little convex, nearly 
flat, the ventral portion is flattened. The umbilicus is extremely narrow. 
The ornamentation consists of strong ribs which begin on the umbilical 

204 University of Texas Bulletin 

border; they are slightly thickened near the umbilical border but do not 
form real nodules. Between these main ribs other secondary ones are in- 
tercalated ; they begin above the umbilical border and are a little less strong 
on the flanks than the main ribs. The ribs are slightly bent forward on 
the flanks but do not considerably increase in strength. Near the ventral 
shoulder the ribs show a tuberculiform thickening and from this point 
bend more strongly forwards ; they end on the ventral shoulder in a strong 
nodule which is longitudinally prolonged. Between the two rows of nod- 
ules on the ventral shoulders we observe an entirely flat and smooth zone 
of the venter ; the ribs do not continue over the ventral portion, but every 
pair of the ventral nodules is connected by a slight thickening, which pro- 
duces on the ventral zone a slight undulation. 

The suture is only partly visible. We recognize the external saddle, the 
first lateral lobe, the first lateral saddle and the second lateral lobe. The 
suture is not very well preserved because this part of the specimen is some- 
what corroded, but still we are able to note the general character. The ex- 
ternal saddle (compare figure) is broad and divided into two parts by a 
rather deep secondary lobe ; the first lateral lobe is broad and shallow, end- 
ing in two points, and on the sides are two rather large branches ; the first 
lateral saddle is higher than the external one, its ramifications are few and 
simple ; the second lateral lobe is much shallower than the first one, and it 
is also narrower and trifid. In this specimen the umbilical portion is not 
preserved but one sees that the second lateral saddle remains rather far 
from the umbilicus, therefore several auxiliary lobes and saddles must have 
existed in the intermediate space. 

Figure 1. Metoecoceras aff. whitei Hyatt, suture 

The ornamentation of our specimens coincides perfectly with that of 
Metoecoceras Whitei Hyatt, only on the ventral part we do not observe as 

A New Ammonite Fauna of the Lower Turanian of Mexico 205 

deep furrows as in Hyatt's plate 13, figure 3, but simply an undulation. As 
far as the suture is visible it corresponds with that of M. Whitei, especially 
with that of plate 14, figure 8 of Hyatt. I do not identify my specimens 
with M. Whitei because they are not sufficiently well preserved, but I am 
sure that they belong to the group of M. Whitei. 

We know very little about the stratigraphic position of M. Whitei; some 
of Hyatt's originals have been found in the Kanab Valley, Utah. According 
to Walcott and Stanton 1 the species occurs there up to a height of 335 feet 
above the base of the Cretaceous. Stanton refers that division to his Colo- 
rado Formation which probably contains several horizons, perhaps from 
the upper Cenomanian, or at least from the lower Turonian to the Emsche- 
rian. For the determination of the age of our beds the species found in the 
United States do not help us much. On the other hand, we do not know any 
European form which might be identified with our species, although this 
has a great similarity with Pulchellia Gesliana Petrascheck from the upper 
Cenomanian of Saxony, as we have shown in the stratigraphical part. 

Number of specimens : 2. 

A//e: Upper Cenomanian (?), lower beds of Cerro del Macho. 

PI. 12, figs. 1-3 

The collection of Dr. Haarmann contains a specimen of Metoecoceras 
which is certainly different from the species described above ; unfortunately 
we do not know in which horizon this specimen has been found ; according 
to its petrographical character it belongs to Horizon I, but it might have 
been found also in Horizon II. Its features are : 

Shell discoidal, very involute, with whorls of a lanceolate cross section 
truncated in the ventral part, much higher than broad. The flanks are a 
little convex, the ventral' portion is flattened. The ornamentation consists 
of rather strong ribs, which are slightly flexuous and which bend forward. 
These begin near the umbilical border, where they are slightly thickened, 
but do not form nodules. Part of these ribs bifurcate below the middle of 
the height of the flank. Between these main ribs we find other secondary 
ones intercalated which begin in different heights of the flank, and which at 
their beginning are less strong than the main ribs. All the ribs show near 
the ventral shoulder a slight thickening of a kind of very low and rounded 
nodules ; on the ventral shoulder the ribs end in a nodule which is longi- 
tudanally elongated. These nodules form together a kind of interrupted 

'Stanton, Colorado Form., p. 35. 

206 University of Texas Bulletin 

keel on both sides of the ventral portion. Between the rows of nodules we 
observe on the ventral portion a rather broad, flat and smooth zone. 

With respect to the involution we observe that the last whorl seems to 
show a tendency to form a wider curve than the preceding whorl. 

No part of our specimen shows a trace of the suture. 

According to its form and ornamentation our specimen belongs certainly 
to Metoecoceras, and I unite it provisionally with this genus although the 
suture is unknown. 

The species differs from M. Whitei Hyatt typus in its' flexuous ribs, but 
it resembles the specimens figured by Stanton 1 in figures 1-2 of plates 38 and 
called Buchiceras Swallovi. Hyatt unites it with his Metoecoceras Whitei, 
notwithstanding that it differs much from the type. It seems that our spec- 
imen has a smaller number of ribs than that figured by Stanton and that the 
ribs are more flexuous. 

Our species resembles much more Pulchellia Gesliniana Petrascheck 2 than 
the above described species. This similarity is really very great but our 
species is distinguished by a smaller number of ribs which are also less 
flexuous. I do not doubt that both species belong to the same group. Meto- 
ecoceras Geslinianum Petrascheck occurs in the upper Cenomanian in 

Number of specimens : 1. 

Age : Upper Cenomanian ( ?) or lower Turonian. 

MAMMITES Laube et Bruder, Emend. Petrascheck 


PI. 12, figs. 6, 8 

In Horizon II of Cerro del Macho there has been found a well preserved 
specimen of Mammites, and also several fragments belonging to the same 
species. They show the following features : 

Shell globose, rather involute, with whorls of a trapezoidal or nearly 
subquadrangular cross section, much broader than high. The umbilicus is 
rounded. On the umbilical border we observe six thick nodules, which are 
rather pointed and a little rounded. In these nodules begin broad, rounded, 
radial ribs, partly simple, partly in pairs. Between these ribs are interca- 
lated generally two secondary ribs also low and rounded, which begin above 
the umbilical border, but without showing nodules at their beginning. On 
these secondary, as well as on the main, ribs we find two strong and rounded 

1 Stanton, Colorado Form. 

2 Petrascheck, Amm. d. sachs. Kreideform., p. 140 (10), pi. 7 (1), figs. 3-5. 

A New Ammonite Fauna of the Lower Turanian of Mexico 207 

nodules near and on the ventral part. These nodules form two rows, each 
of which is composed of 16 to 17 nodules on the last whorl ; those of the row 
on the ventral portion are a little elongated longitudinally. Thus we find 
on each side of the shell three rows of nodules : the umbilical, the interme- 
diate and the ventral row. It seems that the nodules of the intermediate 
row increase in thickness in the front part of the whorl, while those of the 
ventral row decrease a little and extend themselves more longitudinally, 
but none of the specimens is large enough to show the development of the 
nodules in an advanced age. Between the two ventral rows we observe a 
narrow concave zone in the inner whorl and a nearly flat one on the exter- 
nal whorl. 

The suture is very much destroyed but its main features can still be 
recognized. The external lobe is rather deep and narrow, ending in two 
branches ; the external saddle is broad and high, divided into two branches 
by an adventive lobe of relatively great depth ; the first lateral lobe is deep 
and ends in two points ; the first lateral saddle is apparently broad but its 
exact form can not be recognized because the shell is much destroyed in 
this part. 


Diameter 87.0 mm. (1) 

Height of the last whorl 33.0 mm. 0.38 

Width of the last whorl 42.0 mm. 0.48 

Diameter of the umbilicus 23.0 mm. 0.26 

Height of the last whorl in the same diameter but half a whorl 

backwards 30.5 mm. 0.35 

Width of the last whorl in the same diameter and half a whorl back- 
wards 39.0 mm. 0.46 

Our species certainly belongs to the group of Mammites nodosoides 
Schlotheim. Its suture coincides in general fairly well with the one figured 
by Laube and Bruder 1 , but its form and ornamentation resemble more that 
of Mammites conciliatus Stoliczka, 2 which differs from the type of the group 
especially by the greater thickness of the whorl and the more numerous 
nodules on the ventral portion. 

Our species differs from Mammites conciliates by its more involute 
form, the external whorl covering nearly two-thirds of the preceding one. 
barely leaving uncovered the row of umbilical tubercles. We find another 
difference in the number of intermediate and ventral nodules, which is 
much less in our specimen than in the species of Stoliczka. In this direc- 
tion our individuals resemble more the type of Mammites nodosoides, but 

'Laube und Bruder. Amm. d. bohm. Kreide, p. 230. 

2 Stoliczka, Ceph. Cret. Rocks India, p. 99. pi. 50, fig. 4; pi. 51, fig. 1. 

208 University of Texas Bulletin 

they differ from this as well as from M. conciliatus through the small dis- 
tance between the two ventral rows of nodules. In these comparisons I 
take as type of the species M. nodosoides, the specimen figured by Laube 
and Bruder because this comes from the same locality as the originals of 
Schlotheim, which were never figured. 

Similar to our specimens is also the small individual figured by Pervin- 
quiere 1 as a typical M. nodosoides. 

Fritsch 2 figures a Mammites under the name of Ammonites conciliate 
Stoliczka, and Kossmat 3 confirms the conclusion that this specimen is very 
nearly related to the species from southern India; he notes that the main 
difference consists in the involution. In this direction the Mammites con- 
ciliatus Fritsch resembles more our species than that of Stoliczka. Though 
in this latter species the external whorl barely covers the preceding one up 
to the row of intermediate nodules, we observe that in the specimen fig- 
ured by Fritsch the external whorl covers the preceding one nearly to the 
row of umbilical nodules. 

The group of Mammites nodosoides has a quite universal distribution ; 
it is represented in the lower Turonian of all Europe, of Africa, Asia, and 
South America. In North America we probably find it represented by 
Ammonites Loewianus White, 4 an observation previously made by Per- 

Number of specimens: 3. 

Age: Lower Turonian (Salmurian), lower horizon. 

PSEUDASPIDOCERAS Hyatt emend. Pervinquiere 

1902: Mammites Footeanus Stoliczka, Petrascheck, Amm. d. sachs. Kreideform., p. 144, 
pi. 9, fig. 1. 

Among the material collected by Dr. Haarmann in the lower horizon of 
the Turonian of Cerro del Macho is a rather large, not very well preserved 
but quite characteristic cephalopod, showing the following features : 

Shell moderately evolute with whorls of a subrectangular-oval cross- 
section, much higher than broad. The flanks are flattened, the ventral 
portion rounded. The umbilicus is moderately wide, the umbilical wall is 

1 Pervinquiere, Paleontologie Tunisienne, pi. 18, fig. 1. 
2 Fritsch, Ceph. bohm. Kreideform., pi. 7, figs. 1, 2. 
'Kossmat, Siidind. Kreideform., p. 22 (129). 

4 Stanton, Colorado Form., p. 178, pi. 43. figs. 3-4. Some authors write Am laevi- 
anus but it must be Loewianus because the species was dedicated to Dr. Oscar Loew. 

A New Ammonite Fauna of the Lower Turanian of Mexico 209 

abrupt. The ornamentation consists in widely separated, low, rounded, 
nearly straight ribs which begin in a nodule at the umbilical border and 
which end in another very high and pointed nodule at the ventral shoulder. 
Between the two rows of nodules on the ventral part we observe a broad, 
slightly convex and smooth zone. In the last half whorl we count five ribs. 
The suture is not visible. 


Diameter 280mm. (1) 

Height of the last whorl 117 mm. 0.42 

Width of the last whorl 94 mm. 0.34 

Diameter of the umbilicus 104 mm. 0.37 

Our specimen certainly belongs to the group of Pseudaspidoceras Foot- 
eanum Stoliczka, 2 but differs from it by its cross-section which is much 
higher than wide. This is not an absolutely distinctive character because 
we should take into consideration the large size of our specimen and we 
do not know the latest development of the species of Stoliczka. Our speci- 
men resembles Pseudaspidoceras Footeanum Petrascheck more than it 
does the type. The cross-section of the species of Petrascheck is more 
similar to ours and also has widely separated ribs. 

The group of Pseudaspidoceras Footeanum Stoliczka has a very wide 
distribution; it is represented in all the northern part of Africa (we in- 
clude in this group Ps. salmuriense) , in Nigeria, in Portugal, in Saxony, 
and in India. 

Number of specimens : 1. 

Age: Lower Turonian (Salmurian), lower horizon. 

PL 13, fig. 1; PL 15, fig. 1 

1887: Ammonites Pedroanus White, Brazil, p. 212, pi. 22, figs. 1, 2 (not pi. 20, fig. 3). 

In the lower horizon of the Turonian of Cerro del Macho we find a large 
and relatively well preserved specimen which belongs to the group of 
Pseudaspidoceras Footeanum Stoliczka. Its features are: 

Shell large with whorls of a subquadranglar cross-section, nearly as 
high as wide. The flanks are flattened, the ventral portion is nearly flat. 
The umbilicus is relatively wide and deep, the umbilical wall is vertical 
but without a sharp umbilical shoulder. The external whorl covers only 
the ventral portion of the preceding one and leaves the nodules of the ven- 
tral shoulder free. The ornamentation consists of extremely low and 

2 Stoliczka, Ceph. Cret. Rocks India, p. 101, pi. 52, figs. 1, 2. 

210 University of Texas Bulletin 

rounded, nearly straight ribs which sometimes are scarcely perceptible; 
on the last whorl we count thirteen of these ribs. The ribs begin on the 
umbilical border in a strong and pointed nodule and end with another 
and still more prominent but somewhat longitudinally elongated nodule 
on the ventral shoulder. Between the two rows on the ventral shoulders 
we observe a smooth and very slightly convex zone which does not show 
any signs of nodules or ribs ; only the two last nodules seem to be connected 
by a kind of low rounded rib which crosses the smooth zone of the venter. 
Between the nodules of the rows on the ventral shoulder we find some 
ribs or nodules intercalated which do not correspond to umbilical nodules. 

Traces of the suture are visible in different parts but I have not been 
able to draw a complete line. 

Dimensions : 

Diameter: 214 mm. 

The last part of our specimen bemg somewhat crushed and twisted, we 
have taken the following dimensions frcm a little smaller diameter : 

Diameter 164mm. (1) 

Height of the last whorl 63 mm. 0.38 

Width of the last whorl 70 mm. 0.43 

Diameter of the umbilicus 59 mm. 0.36 

Height of the last whorl on the same diameter but half a whorl back- 
wards 42 mm. 0.26 

Width of the last whorl on the same point 45 mm. 0.27 

Our specimen belongs, as we have already mentioned, to the group of 
Pseudaspidoceras Footeanum Stoliczka 1 which it resembles in its involu- 
tion, the cross-section of the whorls, the two series of prominent nodules, 
etc. It differs from the type through its weaker ribs, and the entire ab- 
sence of ribs and nodules on the ventral portion and of a concave zone 
along the line of symmetry on the ventral portion. 

Our species shows much nearer relations to Pseudaspidoceras pedroanum 
White from Brazil than to the type of the group. It has the same kind of 
involution, a very similar cross-section, a nearly identical ornamentation; 
it only seems to differ a little with respect to the nodules on the ventral 
shoulder, which according to the figure of White are connected on the 
last part of the whorl by a kind of low crest, which is also mentioned in 
the text. White also says that in very large individuals the nodules on 
both sides of the venter are connected by a crest which crosses the venter. 
We have indicated a similar phenomenon in the last two nodules of our 
specimen. We thus see that our species resembles in a surprising man- 
ner Ammonites pedroanus Kossmat and others have already recognized 

A New Ammonite Fauna of the Lower Turanian of Mexico 211 

that this species belongs to the group of Pseudaspidoceras Footeanum. 
White compares his species with Ammonites Leonensis Conrad, which is 
probably a Schloenbachia, and also with Prionotropis Woolgari. 

We know nothing about the age of the beds where the type of the species 
has been found but the similarity with Pseudaspidoceras Footeanum allows 
us to conclude that they probably belong to the Salmurian. In this idea 
we are confirmed by the circumstance that in the same locality Vascoceras 
Harttii Hyatt has been discovered. 

Number of specimens : 1. 

Age: Lower Turonian (Salmurian), lower horizon. 

FACES I A Pervinquie're 
PL 14, figs. 1, 2; PL 15, fig. 2 

In the lower bed of the Salmurian of Cerro del Macho Dr. Haarmann 
found a not quite complete specimen of so characteristic a Fagesia that I 
have no hesitation in giving it a new name. Another more complete but 
somewhat deformed specimen collected by Dr. E. Wittich, was given to me 
by Mr. Federico Ritter. The features of the larger specimen are : 

Shell moderately involute with whorls of transversally elliptical cross- 
section, much broader than high. The umbilicus is rather narrow and 
deep; the umbilical wall is abrupt, in the internal whorls nearly vertical. 
The ventral portion is broad and slightly convex, the region of the flanks 
is very narrow and one might say scarcely developed and in reality only 
represented by the umbilical nodules ; the ventral part nearly touches the 
umbilical wall. The ornamentation consists on the umbilical border of 
some nine very strong, pointed and round nodules. From these nodules 
start rounded, broad, rather high ribs which cross the ventral portion 
without interruption in a curve directed toward the front; in general 
a pair of ribs starts from each nodule and one or two more become inter- 
calated between every two pairs. This disposition can not be observed 
with entire certainty because the border of the whorl is a little broken. 

The suture could not be made visible. 


Diameter 165 mm. (1) 

Height of the last whorl 52 mm. 0.32 

Width of the last whorl ?74 mm. 0.45 

Diameter of the umbilicus 66 mm. 0.40 

212 University of Texas Bulletin 

At the first view 1 our species resembles greatly a Stephanoceras, a simi- 
larity which has been noted also in other species of Fagesia especially 
Fagesia superstes Kossmat. 1 From this species, which represents the type 
of the genus, our species differs by being much more evolute and by its 
stronger ribs; the umbilical nodules are less numerous and thicker, the 
ribs are also less numerous and a little stronger. 

Our species is certainly the most evolute one of all the Fagesia so far 
described, but its nearest relative is without doubt Fagesia superstes 
Kossmat. According to the figure published by Kossmat no nodules can 
be seen on the internal whorls, while in our species these nodules can be 
distinguished even on the smallest whorls. 

The occurrence of this species is of certain stratigraphical importance 
in so far as it belongs to a very characteristic group which seems at present 
to be limited to the Turonian. According to Pervinquiere only six species 
are known and all of these belong to the Turonian. Fagesia superstes, 
which resembles ours more than any other species, has been found in 
India (upper Utatur group) and in Tunis (lower Turonian) ; similar forms 
have been discovered in the Turonian of Portugal and France. 2 

Number of specimens : 2. 

Age: Lower Turonian (Salmurian), lower horizon. 

PI. 14, fig. 3 

In the lower horizon of our Salmurian we find a relatively well preserved 
specimen which belongs to Fagesia but differs essentially from the fore- 
going species by its entirely different form and the weaker ornamentation. 
Its general features are: 

Shell subglobose, very involute, with whorls of transversally semilunar 
cross-section. The umbilicus is narrow and deep, the umbilical wall is 
nearly vertical. On the umbilical border of the internal whorls appear 
not very strong nodules; on the last part of the external whorl the um- 
bilical border seems to be entirely smooth. On the internal whorl we 
observe numerous broad and low ribs which are strongest in the central 
part of the ventral portion, while they seem to flatten out toward the 
umbilical border. On the ventral portion the ribs curve slightly toward 
the front. The number of ribs could not be counted because the ventral 

iRossmat, Siidind. Kreideform., p. 26 (133), pi. 6 (17), fig. 1. 
2 Pervinquiere, Paleontologie Tunisienne, p. 325, note 5. 

A New Ammonite Fauna of the Lower Turanian of Mexico 

portion of the last whorl is a little corroded, but there are certainly more 
than forty on the last whorl. The suture is not visible. 


Diameter 94mm. (1) 

Height of the last whorl 36 mm. 0.40 

Width of the last whorl 60 mm. .0.64 

Diameter of the umbilicus 31 mm. 0.33 

Height of the last whorl on the same diameter but half a whorl 

backwards 27 mm. 0.29 

Width of the last whorl at the same point 55 mm. 0.59 

On account of its general form and its ornamentation I place this speci- 
men in the genus Fagesia although the suture could not be made visible. 
Our species is quite similar to Fagesia tevesthensis Peron 1 especially the 
large specimen figured by Pervinquiere- (pi. 20, fig. 6). This individual 
shows on the umbilical border nodules quite similar to those of our speci- 
men. But the African species has much broader and lower whorls which 
in part may be explained by its stage of development, because all the 
species of Fagesia change their cross-section of the whorls with their age 
and grow more rapidly in width than in height. 

Another species which resembles ours is Fagesia rudra Stoliczka. 3 This 
species shows very similar ribs and the umbilical border is entirely smooth. 
Fagesia rudra differs from our species by its much broader and lower 

Unfortunately only a single specimen of our species has been found. 
It was impossible to study the internal whorls in their details and there- 
fore we can not make more detailed comparisons with other species. 

Number of specimens: 1. 

Age: Lower Turonian (Salmurian), lower horizon. 


When Choffat 4 established his new genus Vascoceras he subdivided it 
into four groups: 1. mono-tuberculated forms with wide umbilicus; 
2. subglobose forms with rounded umbilical border ; 3. globose forms with 
angular or subangular umbilical border; 4. multi-tuberculated forms. 
These groups could be called: 1. Group of Vascoceras Gamai; 2. Group 

'Peron, Amm. du Cret. sup. de PAlgerie, p. 23, pi. 7, figs. 2, 3. 
2 Pervinquiere, Paleontologie Tunisienne, p. 325, pi. 20, figs. 5, 6. 
3 Stoliczka, Ceph. Cret. Rocks India, p. 122, pi. 60, fig. 1. 
Choffat, Especes nouv. ou peu conn., p. 51. 

21-1 University of Texas Bulletin 

of Vascoceras Douvillei; 3. Group of Vascoceras harttiiforme; 4. Group 
of Vascoceras subconciliatum. 

Pervinquiere 1 unites the first two groups in one and distinguishes only 
three subdivisions. This seems to me to be the best solution, as the divi- 
sion of the first two groups appears to be rather artificial. 

Among the material of Cerro del Macho we find forms representing the 
three groups. To the first one (in the sense of Pervinquiere) belongs our 
Vascoceras aff. Gamai Choffat and Vascoceras aff. adonense; to the second 
one Vascoceras Angermanni sp. nov., and perhaps Vascoceras aff. arnesense 
Choffat; to the third one Vascoceras mohovanense n. sp. 

The genus Vascoceras so far has been found in Portugal, Spain, Algeria, 
Tunis, Egypt, the Sahara, Nigeria, Brazil, Peru, and Mexico. 

VASCOCERAS sp. nov. ex aff. V. ADONENSE Choffat 
PL 14, fig. 4; PL 17, fig. 2 

1886: Vascoceras adonense Choffat, Especes nouv. ou peu conn., p. 59, pi. 9, fig. 3; 
pi. 21, fig. 12. 

Our specimen shows the following features: 

Internal mold rather large, a little oblique on account of deformation, 
quite evolute, with whorls of a transversally semi-lunar cross-section, 
much broader than high. The umbilicus is wide, the umbilical wall is 
quite abrupt, the umbilical border is rounded and scarcely subangular. In 
the external whorl no nodules exist on the umbilical border; the internal 
whorls are not visible. The surface of the species is smooth, no orna- 
mentation can be distinguished. 

The suture is very simple ; it is not very well preserved but the general 
features can be well distinguished. The external lobe is quite wide and 
not very deep and ends in two branches; the external saddle is wide at 
the base, becoming narrower upward, and is very little ramified; the 
first lateral lobe is funnel shaped, very wide at the mouth ; the first lateral 
saddle is similar to the external one but smaller and inclined toward the 
umbilicus while the external one rather bends over toward the venter; 
the second lateral lobe is funnel shaped, very wide at the mouth and much 
shallower than the first one; the second lateral saddle (on the umbilical 
border) is similar to the first one but smaller. 

The dimensions could not be measured exactly on account of the de- 
formation of the specimen. 

Pervinquiere, Paleontologie Tunisienne, p. 331. 

A New Ammonite Fauna, of the Lower Turanian of Mexico 215 

With respect to its external form our species resembles Vascoceras 
adonense Choffat, but this latter species shows nodules on its umbilical 
border, while these are entirely missing in our specimen. This might be 
explained by the stage of development, our individual being much larger 
than that of Choffat, but our species is certainly much more evolute. A 

Figure 2. Suture, Vascoceras angermanni n. sp. (above) and Vascoceras aff. adonense 
Choffat (below). 

fundamental difference can be found in the suture. In the type species 
we find on the umbilical border the first lateral saddle, but we see that 
in our specimen the second lateral saddle is in this place. In its general 
character our suture is much more similar to that of Vascoceras Gamai. 

Our species therefore has to be considered as a new form which in its 
external figure resembles Vascoceras adonense while the suture places it 
in the vicinity of Vascoceras Gamai. We can not give it a new name 
because the specimen is too badly preserved. 

Number of specimens: 1. 

Age: Lower Turonian (Salmurian), lower horizon. 

2T6 University of Texas Bulletin 

PI. 15, figs. 3-5 

1886: Vascoceras Gamai Choffat, Especes nouv. ou peu conn., p. 54, pi. 7, figs. 1-4; 
pi. 8, fig. 1; pi. 10, fig. 2; pi. 21, figs. 1-5. 

In the collection made by Dr. Angermann I found a cepholopod which 
probably represents a juvenile stage of some species belonging to the group 
of Vascoceras Gamai. Judging from the petrographical aspect of the 
specimen I suppose that it was found in the upper horizon of the Salmurian 
of Cerro del Macho. Its features are : 

Shell relatively small, quite involute with whorls of a subquadrangular 
rounded cross-section, broader than high. The umbilicus is narrow and 
probably deep, the umbilical wall is abrupt. The flanks are flattened, the 
ventral part rounded. On the umbilical border we count seven thick, 
round, and pointed nodules. From each of these starts either a pair of 
ribs or a simple rib, which curves slightly forward and crosses without 
interruption the ventral portion. Between these main ribs one or two 
secondary ones are intercalated. These begin above the umbilical border, 
but on the venter are as strong as the main ones. The ribs are thick, 
broad, rounded, wider than the interstices by which they are separated. 
On the ventral shoulders the ribs seem to have u tendency toward a slight 
thickening but real nodules do not form there. On the anterior part of 
the last whorl, and especially on the ventral region, the ribs seem to dis- 
appear. This region is partially corroded but in a place which is well 
preserved one notes clearly that the ribs are very low and scarcely per- 
ceptible on the line of symmetry. 

Figure 3. Suture, Vascoceras aff. gamai Choffat 

The suture is very little ramified. The external lobe has two branches 
and is quite deep and narrow; the external saddle is little ramified, broad 
and rounded ; the first lateral lobe is less deep than the external one and 
rather narrow. The first lateral saddle is little ramified and resembles in 
its form the external one, but is narrower. 

Our specimen resembles the juvenile form figured by Choffat in figure 4 

A New Ammonite Fauna of the Lower Turonian of Mexico 217 

of plate 7 ; unfortunately no figure of the form viewed from the side has 
been published. The juvenile specimen of figure 3 of plate 7, the lateral 
view of which is given in figure 2 of plate 10 of Choffat is also similar. 
The main difference exists probably in the smaller number of umbilical 
nodules in our specimen and in the narrower cross-section, although this 
latter feature changes with the age. 

In the juvenile specimens of Vascoceras Mundae the ribs are less numer- 
ous and thicker. 

Vascoceras Gamai Choffat occurs in Portugal mainly in the lower and 
middle Turonian of Choffat, both of which according to my opinion belong 
to the Salmurian. 

Number of specimens: 1. 

Age: Lower Turonian (Salmurian), probably from the upper horizon. 

PI. 16, figs. 1-4; PI. 17, fig. 1 

In the collection of Dr. Angermann as well as in that of Dr. Haarmann 
we find a globose cephalopod which at the first view resembles completely a 
Nautilus. In the collection of Angermann there is a small, quite well 
preserved specimen, and in Mr. Haarmann's collection a much larger one, 
but the features of both are the same. There are also a number of frag- 
ments which probably should be united with this singular species. Its 
features are : 

Shell large, globose, extremely involute, with whorls of semi-lunar cross- 
section, much broader than high. The whorls cover the preceding ones 
nearly entirely. The umbilicus is narrow and deep, the umbilical wall 
abrupt, the umbilical border smooth and angular. The surface of the 
shell is entirely smooth without any nodules or ribs. 

The suture is not very well preserved but its general features can be 
well recognized. The external lobe is quite deep and moderately wide, 
ending in two branches. The external saddle is moderately broad, quite 
high, very little ramified ; the first lateral lobe is little ramified, broad, ends 
in two points and is deeper than the external one ; the first lateral saddle 
is broad and rounded, less high than the external saddle. The second lat- 
eral lobe is probably similar to the first but less deep ; it is not entirely pre- 

Dimensions of the smaller specimen : 

218 University of Texas Bulletin 


Diameter 75 mm. (1) 

Height of the last whorl 32 mm. 0.45 

Width of the last whorl 69 mm. 0.92 

Diameter of the umbilicus 14 mm. 0.19 

Height of the last whorl on the same diameter but half a whorl back- 
wards 27 ^..-n. 0.36 

Width of the last whorl at the same point 62 mm. 0.83 

Diameter of the largest specimen : 124 mm. 

Our species resembles greatly Vascoceras Kossmati Choffat 1 ; it is of 
course evident that all the species belonging to this group must be very 
similar, as none of them shows any ornamentation. The main difference 
between our species and Vascoceras Kossmati consists in the different 
curve of the cross section of the internal whorls, which is always of 
greater radius. The suture is also different, the saddles of our species be- 
ing relatively higher and the lobes deeper. One might add that our species 
grows to a larger size than the Portuguese species. 

Vascoceras Kossmati Choffat has been found in Choffat's middle Turon- 
ian of Portugal, which, according to my opinion, belongs to the Salmurian. 
In Egypt it occurs in the lower Turonian. 2 Our larger specimens have 
been found in the upper bed of the Salmurian of Cerro del Macho and the 
specimen collected by Angermann belongs to the same horizon, judging 
from its petrographical character. 

Number of specimens : 3 and several fragments. 

Age: Lower Turonian (Salmurian), upper horizon. 

PI. 18, fig. 12 

Dr. Haarmann found in the upper horizon of Cerro del Macho a cepha- 
lopod, the generic determination of which remains somewhat in doubt be- 
cause its suture can not be made visible. Mr. Frederico Ritter gave me 
another and a little better preserved specimen which shows traces of the 
suture. Their features are : 

Shell subglobose of moderate size, very involute with whorls of semi- 
lunar cross section, broader than high. Flanks and ventral portion round- 
ed. The umbilicus is small and deep, the* umbilical wall is vertical and 
even a little overhanging; the umbilical border is angular. The shell 

1 Choffat, Especes nouv. ou peu conn., p. 63, pi. 13, figs. 8, 9; pi. 14, figs. 1, 2; 
pi. 21, figs. 26, 27. 

2 Eck, Turon in Aegypten, p. 384. 

A New Ammonite Fauna of the Lower Turanian of Mexico 219 

seems to be entirely smooth, no nodules can be observed on the umbilical 
border. The suture is similar to that of the group of Vascoceras Kossmati 
but it is not complete enough for a drawing. 

Dimensions : 

Diameter 106 mm. (1) 

Height of the last whorl 43 mm. 0.41 

Width of the last whorl 72 mm. 0.68 

Diameter of the umbilicus 22 mm. 0.21 

One of the specimens is a little obliquely deformed which makes the de- 
termination still more difficult. The species resembles externally much 
Ammonites arnesensis Choffat 1 , the generic position of which is equally 
doubtful; it seems to me to belong to Vascoceras or to a new subgenous, 
the suture being quite different from that of the type of the genus. 

In one of our specimens the suture is not visible ; in the other one we see 
parts of it which are similar to the elements of the suture of Vascoceras 
Angermanni. Therefore I place our species provisionally in the genus 
Vascoceras. Externally this species resembles somewhat Vascoceras Ar- 
germanm but the umbilicus is wider, the general form less globose, and 
the whorls are less broad in relation to their height. 

Number of specimens: 2. 

Age: Lower Turonian (Salmurian), upper horizon. 

PI. 18, figs. 1-2 

Dr. Haarmann collected in the upper bed of our Salmurian a juvenile 
individual of a cephalopod which certainly represents a new species. Its 
features are : 

Shell small, subglobose, quite involute with whorls of trapezoidal cross 
section, much broader than high. The flanks are somewhat flattened, 
as is also the ventral part. This gives the cross-section its angular form. 
The umbilicus is narrow and deep, the umbilical wall is abrupt, the um- 
bilical border is angular. The ornamentation consists in the last whorl of 
about eleven high and pointed nodules (nearly all broken in the present 
specimen) on the umbilical border; from each of these generally starts a 
pair of ribs. Between this pair of ribs now and then secondary ribs are 
intercalated which begin above the umbilical border. The ribs are thick 

'Choffat, Especes nouv. ou peu conn., p. 68, pi. 13, fig. 10 ; pi. 14, fig. 3, pi. 22, fig. 39. 

220 University of Texas Bulletin 

and high. They become a little lower on the venter but cross it without 
interruption; no longitudnal furrow exists on the venter. On the ventral 
shoulders the ribs thicken a little, forming on each shoulder a row of ra- 
dially elongated nodules ; these are not very strong and rather low. These 
nodules make the ventral shoulders appear angular and the ventral zone 
more flattened than concave. 

Figure 4. Sutures, Vascoceras mohovanense n. sp (above) and Mammites mohovan- 
ensis n. sp. (below). 

The suture is very simple. The external lobe is quite wide and deep, 
and bifid ; the external saddle is broad, low, or a rounded form and a little 
ramified ; the first lateral lobe is wide, approximately as deep as the exter- 
nal lobe but much wider, and it ends in two points ; the first lateral saddle 
is very low, rounded and broad and lies in the umbilical nodule; the form 
of the second lateral lobe, which lies mostly on the umbilical wall, can not 
be well distinguished. 

Dimensions : 

Diameter 56 mm. (1) 

Height of the last whorl 21 mm. 0.38 

Width of the last whorl 45 mm. 0.80 (with the nodule) 

Diameter of the umbilicus 19 mm. 0.34 

Height of the last whorl on the same diameter but 

half a whorl backwards 16 mm. 0.29 

Width of the last whorl at the same point 34 mm. 0.61 

This very characteristic species certainly belongs to the group of Vasco- 
ceras sub conciliation Choffat 1 , but it resembles Vascoceras polymorphum 

1 Choffat, Espfcces nouv. ou peu conn., p. 64, pi. 15, figs. 1-3; pi. 16, fig. 4; pi. 22, 
figs. 28-31. 

A New Ammonite Fauna of the Lower Turanian of Mexico 221 

Pervinquiere 1 more than it does the type. From both species it differs 
through the absence of an intermediate row of nodules and consequently 
through the different cross section of tne whorl. From Vascoceras subcon- 
ciliatum our species is also distinguished by its very reduced and simple 
suture. In this case it resembles much more Vascoceras polymorphum 
Pervinquiere, which shows a very similar suture. 

Pervinquiere has extensively discussed the relations of Vascoceras poty- 
morphum with the other Vascoceras, as well as with Mammites and Acon- 
thoceras, indicating the similarity of certain groups of Aconthoceras and 
Mammites, and emphasizing the singular nature of the suture, which is 
similar to that of other Vascoceras. I believe that Pervinquiere's reasons 
are well founded and that the present group should be placed in the genus 
Vascoceras, especially as this genus is nearly related to Acanthoceras and 
Mammites; therefore the similarity between certain groups of the three 
genera is not very surprising. 

Vascoceras polymorphum Pervinquiere occurs in the lower Turonian of 
Tunis; Vascoceras subconciliatum Choffat is found in beds of a similar 
age in Portugal. Pervinquiere also emphasizes the similarity between this 
group and a cephalopod from Brazil, Ammonites offaccinatus White, 2 but 
this latter species is too little known to allow a detailed comparison. The 
suture is not figured but according to White it is rather complicated. It 
is therefore possible that it belongs to a different group, or even to a dif- 
ferent genus. 

Number of specimens : 1. 

Age: Lower Turonian (Salmurian), lower horizon. 


PI. 18, figs. 3, 10, 13 

1907: Neoptychites cephalotus Courtiller Pervinqutere, Paleontologie Tunisienne, p. 393, 
pi. 27, figs. 1-3. Cum syn. 

Among our material exists a cephalopod of small size which in its ex- 
ternal form and its suture resembles the juvenile specimens of Neoptychi- 
tes. Its features are : 

Shell subglobose, very involute, last whorl broader than high with nearly 

Pervinquiere, Paleontologie Tunisienne, p. 336, pi. 21, figs. 2-5. 
'White, Brazil, p. 219, pi. 23, figs. 3, 4. 

222 University of Texas Bulletin 

semilunar cross-section. The umbilicus is very narrow; the wall can not 
be seen. The flanks are slightly convex, the venter is rounded. The orna- 
mentation consists of low, rounded, broad, numerous ribs (about 32 to the 
whorl) which apparently do not reach down to the umbilical region and 
which are strongest on the ventral portion. On the internal whorl we note 
a well defined and rather broad constriction which toward the front is 
limited by a slight thickening ; the constriction is especially evident on the 
venter. The ribs are curved forwards, as is the case with the constriction, 
although in less degree. 

Figure 5. Suture, Neoptychites aff. cephalotus Courtiller 

The suture is very similar to that of Neoptychites and corresponds in 
general to that of Neopychites cephalotus, although the figure published by 
Pervinquiere is taken from a much larger specimen ; a little more similar 
still is the suture of the small specimen of N. xetriformis, in the above cited 
work of Pervinquiere (p. 398, fig. 153) , although there the external saddle 
is more slender than in our specimen. The suture of our individual is not 
complete and in some places can not be very well followed, but in general 
narrow, ending in two branches; the external saddle is quite broad and 
one recognizes the main features. The external lobe is deep and relatively 
high and little ramified ; the first lateral lobe is a little shallower than the 
external one, ends in two points and shows also a branch directed obliquely 
toward the ventral region ; the first lateral saddle is similar to the external 
one but is lower and narrower. 

Figure 6. Suture, Neoptychites aff. cephalotus Courtiller 

Dimensions : 

Diameter ............................................. ...... 50mm. (1) 

Height of the last whorl ............................ ^ ........ 2<5 mm. 0.52 

Width of the last whorl ...... .......................... " . . ...... 33 mm. 0.66 

Our specimen represents the juvenile stage of a Neoptychites similar to 
the one figured by Pervinquiere in pi. 27 fig. 2, which it resembles much in 
its external features ; it differs mainly in its great width. But according to 
Pervinquiere the dimensions change much in the genus, and we should not 
give too much importance to this feature. A specific determination of our 

A New Ammonite Fauna of the Lower Turanian of Mexico 223 

specimen is not possible on account of its small size ; we can only say that 
it is a Neoptychites similar to Neoptychites cephalotits but probably a dif- 
ferent species. 

Neoptychites cephalotus occurs in the lower Turonian of Tunis, Altrerla 
and France. Grossouvre proposes to unite it with Neoptychites Telinga. 
Stoliczka and Pervinquiere accepts this opinion. There is no doubt that 
the adult individuals of the two species resemble each other very much, 
although the suture seems to be somewhat different and a little more rami- 
fied in N. cephalotus; but this last character is not decisive as long as we 
know only the suture of a very large specimen of N. Telinga.. A definite 
result can only be reached through the study of the development of N. Te- 
linga or at least of that of small specimens. 

Number of specimens : 1. 

Age: Lower Turonian (Salmurian), upper horizon. 

PL 18, figs. 9, 11 

1907: Neoptychite xetriformis Pervinquiere, Paleontologie Tunisienne, p. 398, pi. 27, 
figs. 5-7. 

Among the material collected by Dr. Angermann is a very typical Neop- 
tychites. The specimen is sufficiently well preserved for a generic deter- 
mination. Its features are : 

Shell discoidal, very involute, with whorls of nearly sagittiform cross 
section, much higher than broad. The greatest width is near the umbilical 
border. The flanks are quite flattened and very little convex, and the ven- 
ter is rounded. The umbilicus is extremely narrow and deep ; the umbil- 
ical wall is vertical ; apparently a slight thickening exists on the umbilical 
border, at least in the last part of the external whorl. On the flanks we 
observe radial, broad, low, and rounded ribs which are strongest in the 
region near the venter and which decrease in strength toward the umbilical 
as well as toward the ventral region ; they disappear near the umbilicus. 
On the venter the ribs are very low and scarcely discernible ; near the ven- 
tral portion, they bend forward. The number of ribs could not be counted 
because part of the surface is corroded. 

The suture is not very well preserved but the main features can be rec- 
ognized. The external lobe is relatively wide and shallow, ending in two 
short branches; the external saddle is not very high nor very broad but 
little ramified. The first lateral lobe is wide and ends in two points ; it also 
has a branch on each side, and is deeper than the external lobe. The first 

224 University of Texas Bulletin 

lateral saddle is narrow, a little lower than the external saddle, and little 
ramified ; second lateral lobe is similar to the first in its form but smaller 
and much shallower ; the second lateral saddle is very low and very broad 
and of oblique form. 

Dimensions : 

Diameter 73 mm. (1) 

Height of the last whorl 40 mm. 0.55 

Width of the last whorl 33 mm. 0.45 

Diameter of the umbilicus 6.5 mm. 0.09 

With respect to its external form our specimen is very similar to Neop- 
tychites xetriformis; even the dimensions coincide sufficiently, if we take 
into consideration the variability of Neoptychites. The main difference 
consists in the ornamentation; the ribs are much more numerous in our 
species (probably 25 to 30 on the last whorl) and they do not disappear 
completely on the venter. The specimen thus occupies an intermediate 
position between N. cephalotus and N. xetriformis, or between this and 
2V. xetra, if the small individual figured by Stoliczka 1 really belongs to N. 
Xetra. The suture of our specimen resembles that of N. Xetra still more 
than that of N. xetriformis. 

N. xetriformis occurs in the lower Turonian of Tunis. N. Xetra 
Stoliczka belongs to the lower and middle Utatur group according to Koss- 
mat, but we should not forget that the determination of the horizons of 
the Utatur group is in general based on the petrographical character of 
the fossils and on the locality. The determination of the age is therefore 
not always certain for each species. How doubtful it sometimes is we can 
see in our own case. On page 168 (72) Kossmat cites N. Xetra from the 
lower and middle Utatur group; on page 196 (131) he cites it from the 
lower and upper Utatur group. This doubt with respect to the age of the 
different species can not surprise us. because Kossmat could not base his 
determinations on well divided and stratigraphically well studied cross 
sections, but rather on general observations and subdivisions based more 
on the petrographical character of the rocks than on the faunas. Kossmat 
himself (loc. cit. p. 132 (197)) is convinced that a paleontological and 
stratijrraphical subdivision of the Utatur group is possible, but until this 
has been executed in a modern manner, we should not crive too much im- 
portance to the age which has been assigned to a certain species from In- 
dia. We should always take into account that in such old collections labels 

'Stoliczka, Ceph. Cret. Rocks India, pi. 61, fig. 2. 

A New Ammonite Fauna of the Lower Turanian of Mexico 225 

may have been changed and that the fossils frequently have not been col- 
lected with the necessary exactness. 

Number of specimens : 1. 

Age: Lower Turonian (Salmurian), lower horizon. 

HOPLITOIDES V. Koenen Emend. Solger et Pervinquiere 

The genus Hoplitoides has been established by von Koenen 1 for certain 
ammonites from the limestones of the Mungo in Kamerun; later Solger 2 
studied the same fauna and made the definition of the genus more precise. 
Then Pervinquiere 1 amplified this definition still more and distinguished 
two groups within the genus Hoplitoides: the bicarinate and the monocar- 
inate forms. The first group seems to be limited to the Turonian, the sec- 
ond one to the Emscherian. 

Among our material we find a few ammonites which very probably be- 
long to the first group, the bicarinate Hoplitoides. The specimens are not 
very well preserved and the generic determination is not entirely certain. 
The external form corresponds completely with that of the Hoplitoides, 
but the suture is much destroyed and scarcely permits recognition of the 
general character of the line; this, however, coincides entirely with the 
suture of the bicarinate Hoplitoides. The character of the suture on the 
other hand shows that the specimens do not belong to Placenticeras, a 
genus which externally is quite similar to Hoplitoides. 


PI. 19, figs. 1-3 
1907 : Hoplitoides mirabilis Pervinquiere, Paleontologie Tunisienne, p. 218, pi. 10, fig. 3 

Among the material placed at my disposition I found two relatively 
complete specimens and four fragments which, according to their suture 
and external form, belong to the so-called Pseudoceratites of the Creta- 
ceous. The best preserved specimen shows the following features : 

Shell discoidal, entirely evolute, with whorls of lanceolate cross section 
truncated at the point, much higher than broad. The umbilicus is very 
narrow, the umbilical wall is vertical and the umbilical border rounded. 
The flanks are smooth, very little convex, nearly flat. The venter is flat 
with a sharp shoulder on each side; on the internal whorl we observe on 
both shoulders of the venter a sharp keel and the zone there is concave. 

J v. Koenen, Nachtr. Foss. Mungo i. Kamerun, p. 53. 
2 Solger, Mungokreide, p. 127. 


University of Texas Bulletin 

The suture is badly preserved, because all the specimens are corroded 
on the surface, and rio suture could be made visible on the internal whorls. 
We note a little ramified external saddle, which is rather broad and low; 
the first lateral lobe is broad, shallow and ends in three points, those on 
the umbilical side being longer than the one on the ventral side. Some 
smaller ramifications exist on the sides of this lobe. The first lateral 


Figure 7. Sutures, Neoptychites aff. xetriformis Pervinquiere (lower left hand corner) 
and Hoplitoides sp. (other three). 

saddle is broad and relatively high, and a secondary lobe divides it in two 
parts. The following saddles are much destroyed and no longer show 
their ramifications. The lobes are much shallower than the first lateral 

Dimensions : 

Diameter 149 mm. (1) 119 mm. (1) 

Height of the last whorl 76mm. 0.51 58mm. 0.49 

Width of the last whorl 45mm. 0.30 34mm. 0.29 

Diameter of the umbilicus 19 mm. 0.13 18 mm.? 0.15 

Our specimens belong very probably to the genus Hoplitoides and to the 
bicarinate group of it. Externally they resemble this group in an extra- 
ordinary manner and especially Hoplitoides mirabilis Pervinquiere. Per- 
vinquiere has united these forms, which distinguish themselves by a flat 
venter even in a very advanced stage, with the Hoplitoides of the Emsche- 
rian, which show a flat venter only in their youth, the venter in the adult 
age becoming sharp or a little rounded. Only the study of a large and 

> A New Ammonite Fauna of the Lower Turanian of Mexico 227 

rich material could decide if it would not be better to separate these two 
groups at least subgenerically. It was probably the want of sufficient ma- 
terial which decided Pervinquiere not to separate the two Turonian species 
from the rest of the genus. If such study should prove that all the species 
from the Turonian belong to .the bicarinate group, it would be better to 
unite them in a different species. 

The main difference between our species and H. mirabUis consists prob- 
ably in the larger diameter of the umbilicus, but our material is not suffi- 
ciently well preserved to allow a more detailed comparison. 

The two species of bicarinate Hoplitoides described by Pervinquiere oc- 
cur in the lower Turonian ; one of them has also been found in the upper 
Turonian (H. Munieri). 

Eck 1 cites with some doubt Hoplitoides mirabilis, or a similar form, from 
the Turonian of Egypt. Woods 2 describes a Hoplites Nigeriensis from Ni- 
geria which he takes to belong to the bicarinate Hoplitoides. These spec- 
imens occur in probably Turonian beds. In the same locality have been 
found Vascoceras Gongilense Woods and Pseudaspidoceras sp. Woods 
mentions that Hoplitoides has also been found in another locality of Ni- 

Number of specimens : 2, and 4 fragments. 

Age: Lower Turonian (Salmurian), upper horizon. 


AVICULA Bruguiere 


PI. 20, figs. 1-2, 11-12 

The material from the upper horizon of the Salmurian of Cerro del 
Macho contains a number of specimens of a large and well characterized 
Avicula. Its features are : 

Shell thin, of subquadrate form, nearly as high as broad, not very con- 
vex ; the right valve is a little more convex than the left one. On the an- 
terior side is a prolongation in form of an auricula which is not quite com- 
pletely preserved but which certainly was not very long ; on the posterior 
side we note a prolongation in form of a wing, with a precise limit be- 
tween this wing and the rest of the shell. The auricula as well as the wing 

!Eck, Turon in Aegypten, p. 382 and 386. 

2 Woods, Cret. dep. Northern Nigeria, p. 284, pi. 23, fig. 3; pi. 24, figs. 1-5; fig. 1 
of the text. 

228 University of Texas Bulletin 

form with their superior border approximately the prolongation of the 
cardinal border and do not elevate themselves above the beaks. The beaks 
are small and pointed. The cardinal border is straight, long, and vertical 
in relation to the longitudinal axis of the shell. The surface of the shell 
is entirely smooth and shows only fine concentric striae of growth. All 
our specimens are internal molds but some have preserved remains of the 

Our very characteristic species resembles Av icula gravida Coquand. 1 The 
main difference seems to consist in the greater convexity of the valves in 
this latter species, also in the different position of the beaks in relation to 
the upper border of the auricula and the cardinal border ; but it is possible 
that this last difference may be explained as an error of the draftsman, 
because Coquand mentions expressly that neither the auricula nor the pos- 
terior wing elevate themselves above the beaks. In every case our species 
is nearly related to the African one. 

Coquand mentions that his species occurs in the Turonian (Mornasian) 1 ; 
later on Peron 2 corrected this determination of the horizon. He says that 
he has always found this species in the Santonian, at the ^ase of the Se- 
nonian, in the beds with Buchiceras and Hemiaster Fourneli. But not- 
withstanding this correction it is possible that Coquand was right in his 
determination of the horizon, because Pervinquiere 3 also mentions that he 
has found Avicula gravida in the lower Turonian. The species seems to 
occur also in the Emscherian, from which horizon it is cited by Pervin- 
quiere 4 who has also found it at the base of the Senonian immediately 
above the Turonian. The species thus probably lived from the Salmurian 
to the Senonian; it is of course possible that the specimens found in the 
different horizons really were different species, although these certainly 
belong to the same group. 

At first view, one might believe that our species are identical with Avi- 
cula pedernalis Roemer 1 but Avicula Aguilera does not have the singular 
scars of that species, which remind us of those of Meleagrina. Roemer 
has figured them and I have observed them also on a specimen from the 
Vraconian of Arivechi, Sonora. The general form of Roemer's species is 
also a little different from ours. 

Number of specimens : 6. 

Age: Lower Turonian (Salmurian), upper horizon. 

Coquand, Geol. et Pal. de Constantine, p. 216, pi. 13, figs. 17, 18. 
2 Thomas et Peron, Hauts-Plateaux de la Tunisie, p. 241. 
3 Pervinquiere, Et. geol. Tunisie, pp. 101, 108. 
4 Pervinquiere, Et. geol. Tunisie, p. 115, 117, 151. 

A New Ammonite Fauna of the Lower Turanian of Mexico 229 



PI. 20, fig. 5 

1813: Oxtracites labiatus Schlotheim in Leonhard's min. Taschenb. VII p. 93, fide 


1875: Inoceramus labiatus Geinitz, Elbthalgebirge II, p. 46, pi. 12 cum syn. 
1893: Inoceramus labiatus Stanton, Colorado Form., p. 77, pi. 10, fig. 4; pi. 14, fig. 2 

cum syn. 
1903: Inoceramus labiatus Petrascheck, Inoc. a. Kr. Bohmens, p. 156. 

In the upper horizon of the Salmurian of Cerro del Macho, Dr. Haar- 
mann found four Inoceramus of which at least three are typical Inoceramus 
labiatus Schlotheim. They are relatively small individuals but are en- 
tirely identical with those from Parras, Mexico, and different European 
localities. I have discussed this species extensively in Boletin 30 of the 
Institute Geologico de Mexico; a detailed description of the specimens 
found on Cerro del Macho does not seem to be necessary. 

The occurrence of this species at our locality is of some importance 
because the determination of the age of the Mexican Turonian beds up 
to the present is entirely founded on bivalves, especially Inoceramus, and 
this class of fossils is always stratigraphically of less value than the 
cephalopods. My former determinations are now confirmed by the. oc- 
currence of Inoceramus labiatus together with typical ammonites of the 
lower Turonian. 

Up to the present, Inoceramus labiatus has not yet been found in the 
lower beds of our Salmurian ; it only occurs in the upper one, and even 
there it is not very frequent. Of course we can not yet draw any con- 
clusions from this distribution. The stratigraphical conditions of the 
region of Mohovano should first be studied with care, larger collections 
from the lower horizons should be made, so as to show if Inoceramus 
labiatus really does not appear in those beds ; and finally the relation be- 
tween the cephalopod beds and the shales with Inoceramus of other re- 
gions of northern Mexico should be ascertained. 

Number of specimens: 3 (4?). 

Age: Lower Turonian (Salmurian), upper horizon. 

230 University of Texas Bulletin 


PL 18, figs. 4-8 

In the lowest beds of Cerro del Macho numerous specimens of an en- 
tirely smooth Exogyra have been found. This species resembles to a 
certain degree Ex. columba Lamarck but is not completely identical with 
it._ Its character is : 

Larger valve thin, very convex, especially in the central portion, thus 
forming a kind of rounded crest which goes from the beak to the lower 
margin. This crest gives the shell an asymmetric aspect because it is not 
entirely in the center, but a little nearer the anterior margin ; this asym- 
metry is particularly noted in large specimens and much less in juvenile 
individuals. The beak is quite slender, spirally coiled at its point. The 
valve is broad, without forming wings and without a furrow in any of 
the sides. From the above mentioned crest the shell slopes rapidly toward 
the anterior margin and slowly toward the posterior margin. The sur- 
face is entirely smooth, showing only fine striae of growth and in a large 
specimen there is an indication of two slight concentric ridges, certainly 
produced by the manner of growth. 

The smaller valve is nearly flat. In none of the specimens is the surface 
entirely preserved and a detailed description of this valve can not be made. 

Oar species resembles Ex. columba Lamarck but is much smaller and 
never shows a radial ornamentation, and the rounded crest is nearer to 
the anterior margin while in the European species it is nearer the posterior 

In its shape our species resembles still more Ex. columbella Meek, 1 
especially on account of the position of its crest, but the radial ornamenta- 
tion of that species is entirely missing in ours. 

Number of specimens : 12 and numerous fragments. 

Age: Upper Cenomanian?, lower beds of Cerro del Macho. 


1850: Exogyra olisiponensis Sharpe, Secondary Distr. of Portugal, p. 185, pi. 19, 

figs. 1, 2. 
1911 : Exogyra olisiponensis Woods, Cret dep. Northern Nigeria, p. 278, pi. 20, figs.1-3. 

cum syn. 

In the upper part of the marls which we believe belong to the Ceno- 
manian, Dr. Haarmann found a fragment of a large Exogyra. This 

'Stanton, Colorado Form., p. 63, pi. 8, figs. 2-4. 

A New Ammonite Fauna of the Lower Turanian of Mexico 231 

species is distinguished by a moderately broad and coiled beak which slopes 
quickly toward the anterior margin; this steep slope continues on the 
valve itself, while toward the posterior margin the valve slopes in a very 
regular curve. The ornamentation consists of radial, thick, and not very 
numerous ribs. Where these are crossed by specially strong concentric 
lamellae of growth, a kind of prolongations is formed which nearly re- 
semble spines. The shell itself is very thick. 

The specimen does not seem to be very nearly related to the Exogyra 
with radial ribs, of the Mexican middle and upper Cretaceous (Ex. Whit- 
neyi, Ex. costata, etc.) but much more to the varieties with few ribs be- 
longing to the group of Ex. Olisiponensis from the border of the Med- 

Our fragment is especially similar to an individual from the Cenoma- 
nian of Wadi Am Rimpf figured by Fourtau 1 ; this specimen shows a very 
similar ornamentation. 

Very similar also are some specimens from Deba Habe in Nigeria figured 
by Woods ; these show particularly the strongly sloping region of the shell 
toward the anterior margin. 

Exogyra olisiponensis occurs in the Cenomanian as well as in the Turo- 
nian. Many authors certainly take the species in a very wide sense and 
we do not yet know if it is possible to separate specifically the form of the 
Cenomanian from that of the Turonian. In general it seems to me that 
our specimen resembles more the varieties figured from the Cenomanian 
(compare among others Lartet, Geol. de la Palestine, pi. 11, fig. 1) than 
those from the Turonian. With this view the layer in which our specimen 
has been found coincides well; it occurs in the upper part of the marly 
limestones directly below the Salmurian of Cerro del Macho. We have 
considered these marls with some doubt as upper Cenomanian. Unfortu- 
nately we do not know the exact stratigraphic position of the individuals 
from Nigeria. Woods presumes that they come from the Turonian, be- 
cause in Gongila, in Nigeria, not only typical cephalopods of the Turonian 
(Vascoceras, Pseudaspidoceras, bi-carinated Hoplitoides) have been found, 
but also specimens of Exogyra olisiponensis, while in Deba Habe only 
Ex. olisiponensis has been collected. A solution of this problem is im- 
possible for the moment, but there is the possibility that at Deba Habe the 
Cenomanian might be represented by beds with Ex. olisiponensis. 

Number of specimens: 1. 

Age: Upper Cenomanian (?), upper part of the lowest horizon 6f 
Cerro del Macho. 

'Fourtau. Faune cret. d'fegypte, p. 287, fig. 5. 

232 University of Texas Bulletin 



PL 20, fig. 3 
1849: Tylostoma ovat-um, Sharpe, On Tylostoma, p. 379, pi. 9, figs. 7, 8. 

In the upper horizon of our Salmurian numerous specimens of gastro- 
pods have been collected; among these Tylostoma or similar genera seem 
to predominate. The greater part consists of internal molds which are 
badly preserved. In some specimens we note that the labrum is thick- 
ened on the inner side, thus these individuals very probably belong to 
Tylostoma. It is very possible that there are different species in the col- 
lection but in consideration of the bad state of preservation of the ma- 
terial it is impossible, to distinguish them with certainty. The best speci- 
men, as well as some less well preserved, has much similarity with T. ova- 
turn Sharpe. Its features are: 

Shell subglobose, of broad oval form, with a low spire of approximately 
six coils, mouth suboval and relatively narrow, labrum having an inner 
thickening. The surface is entirely smooth. 

According to Choffat 1 T. ovatum occurs in all the beds from the Bella- 
sian to the upper Turonian ; it is thus not very surprising that a similar 
form is found in our beds. 

Number of specimens : 5 and probably numerous fragments. 

Age: Lower Turonian (Salmurian), upper horizon. 



PI. 20, figs. 6-10 

In the lower marls of Cerro del Macho, Dr. Haarmann found a Hemiaster 
which probably represents a new species. He found another specimen 
loose below the hill which seems to belong to the same species, but it is 
too badly preserved for determination. The features of the better pre- 
served specimen are : 

'Choffat, Syst. cret. Portugal II, p. 190. 

A New Ammonite Fauna of the Lower Turanian of Mexico 233 

Shell of small size, little convex, slightly polygonal in the ambitus, thin- 
ning toward the back and toward the front, the greatest width lying far 
in front of the center of the shell ; slightly notched in front and truncated 
behind. The upper face is convex, the ambitus rounded, the lower face 
is nearly flat, a little thickened on the plastron and slightly depressed in 
the region of the peristome. 

The impair ambulacrum lies in a relatively broad and moderately deep 
furrow which begins in the apex and from these regularly widens toward 
the ambitus, narrowing from there to the peristome; the furrow notches 
the contour considerably. The zones of pores are composed of pairs of 
small, nearly circular pores; the pores of each pair seem to be separated 
by a slight thickening. The zone is wide and nearly smooth ; large tuber- 
cles are missing there and only the fine granulation can be observed. The 
zones of pores occupy less than half the furrow between the apex and the 
ambitus. Farther on follow pores separated by larger intervals and of 
an oblique position, arranged in such a manner that the pairs of the two 
zones alternate. The exact number of these pairs could not be counted. 

The anterior paired ambulacra are moderately large and of lanceolate 
form ; they lie in relatively deep furrows. The poriferous zones are broad 
and consist of pairs of elongated, nearly equal pores ; the pores of each pair 
are connected by a very distinct furrow. The interporiferous zone is rela- 
tively narrow and has not quite the width of one of the poriferous zones. 

The posterior paired ambulacra are a little shorter than the anterior 
ones. The poriferous zones consist of pairs of elongated nearly equal 
pores; the pores of each pair are connected by a slight furrow. The in- 
terporiferous zone is rather narrow and less wide than each of the porif- 
erous zones. Outside of the petals the pores are smaller and the pairs 
are separated by large intervals. 

On the whole surface of the interambulacra we observe apparently cren- 
ulated and perforated tubercles, enclosed by narrow areas and very near 
together; they are stronger on the anterior portion than on the posterior 
one. In the interporiferous zones of the ambulacra of the upper face, 
tubercles do not seem to exist. In the ambulacra of the lower face tuber- 
cles are infrequent, while the interambulacra of the same face are densely 
covered by tubercles, especially the plastron; they decrease in size from 
the center toward the outside. The whole surface of the shell is covered 
by a fine granulation. 

The impair posterior inter-ambulacrum of the upper face has a sharp 
crest which is higher than the apicial apparatus. The anterior interam- 
bulacra of the same face show much less pronounced crests; the lateral 
interambulacra are flattened on the center, the flattened zone being lim- 

234 University of Texas Bulletin 

ited by well marked borders. These margins and the crests of the other 
interambulacra give the polygonal contour to the figure of the shell. 

The peristome is small and of subpentagonal form. Its position is ex- 
centric toward the front; the lip is rather prominent. The periproct is 
not well preserved, but is of oval form and lies in the upper part of the 
posterior face. The apicial apparatus is relatively large, the two posterior 
pairs are widely separated from the anterior ones ; the details can not be 
clearly recognized. 


Antero-posterior diameter 27.8 mm. 

Transversal diameter 27.3 mm. 

Height 19.0 mm. 

Distance between the apex and the posterior margin 16.2 mm. 

Our species is not very characteristic but I have not found one with 
which it might be identified entirely. It resembles to a certain degree 
Hemiaster Meslei Peron et Gauthier, 1 but in this species the posterior am- 
bulacra diverge much more than in ours, the contour is more notched in 
front, the furrow of the impair ambulacra is much narrower and deeper. 

As we have not more than one well preserved individual I only describe 
and figure it without giving a new name to this species, or identifying it 
with a known one. 

Number of specimens: 2. 

Age : Upper Cenomanian ( ?) , lower horizon of Cerro del Macho. 

l Cotteau, Peron et Gautheir, Ech, foss. de 1'Algerie IV, p. 102, pi. 2, Igs. 5-8. 


Metoecoceras, Fagesia, Mammites 

236 University of Texas Bulletin 

Metoecoceras, Fagesia, Mammites. Plate 12 

Figures 1, 2, 3. Metoecoceras sp. nov page 205 

Upper Cenomanian (?) or lower Turonian. Cerro del Macho, Hacienda de Moho- 

vano, Coahuila. 

Fig. 1. View from the opposite side from Figure 3. 
Fig. 2. Venter of the same specimen. 
Fig. 3. Side view. 

Figures 4, 7. Metoecoceras aff. Whitei Hyatt page 203 

Upper Cenomanian (?), lower horizon of Cerro del Macho, Hacienda de Moho- 

vano, Coahuila. 
Fig. 4. Venter. 
Fig. 7. Side view. 

Figure 5. Fagesia Pervinquieri sp. nov page 212 

Lower Turonian, lower horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 
Venter and cross-section. 


Figures 6, 8. Mammites mohovanensis sp. nov page 206 

Lower Turonian, lower horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 
Fig. 6. Cross-section and venter. 
Fig. 8. Side view. 

University of Texas Bulletin No. 1856 

,'. 'Flate 12 



238 University of Texas Bulletin 


Pseudaspidoceras Plate 13 

Figure 1. Pseudaspidoceras aff. Pedroanum White sp page 209 

Lower Turonian, lower horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 

Side view. 

University of Texas Bulletin No. 1856 

Plate 13 


Fagesia, Vascoceras 

240 University of Texas Bulletin 


Fagesia, Vascoceras Plate 14 

Figure 1. Fagesia Haarmanni sp. nov page 211 

Lower Turonian, lower horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 

View of the other side of the specimen figured as Fig. 2, PI. 15. 

Figure 2. Fagesia Haarmanni sp. nov page 211 

Lower Turonian, lower horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 
Cross-section and venter of specimen figured as Pis. 15 and 14. 

Figure 3. Fagesia Pervinquiri sp. nov page 212 

Lower Turonian, lower horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 
Side view of specimen figured on PI. 12, fig. 5. 

Figure 4. Vascoceras n. sp. ex. aff. V. adonense Choffat page 214 

Lower Turonian, lower horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 
Cross-section and venter. 

University of Texas Bulletin No. 1856 

I M.,..- 14 


Pseudaspidoceras, Fagesia, Vascoceras 

242 University of Texas Bulletin 


Pseudaspidoceras, Fagesia, Vascoceras Plate 15 

Figure 1. Pseudaspidoceras aff. Pedroanum White sp page 209 

Lower Turonian, lower horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 

Cross-section and venter. 

Figure 2. Fagesia Haarmanni sp. nov page 211 

Lower Turonian, lower horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 
Side view. 

Figures 3, 4, 5. Vascoceras aff. Gamai Choffat page 216 

Lower Turonian, probably from upper horizon. Cerro del Macho, Hacienda de 

Mohovano, Coahuila. 
Figs. 3 and 5, view of both sides. 
Fig. 4. Cross-section and venter of the same specimen. 

University of Texas Bulletin No. 1856 

Plate IS 



244 University of Texas Bulletin 


Vascocera* Plate 16 

Figures 1, 2, 3, 4. Vascoceras Angermanni sp. nov page 217 

Lower Turonian, upper horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 

Fig. 1. -Side view. 

Fig. 2. Cross-section and venter of specimen figured on Fig. 4. 

Fig. 3. Cross-section and venter. 

Fig. 4. Side view of a larger specimen. 

University of Texas Bulletin No. 1856 

Plate 16 


246 University of Texas Bulletin 


Vi.coceras Plate 17 

Figure 1. Vascoceras Angermanni sp. nov , page 217 

Lower Turonian, upper horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 

Side view of a large specimen. 

Figure 2. Vascoceras n. sp. ex. aff. V. adonense Choffat. page 214 

Lower Turonian, lower horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 
Side view of the specimen figured on PL 14, fig. 4. 

University of Texas Bulletin No. 1856 

Plate 17 





Vascoceras, Neoptychites, Exogyra 

248 University of Texas Bulletin 


Vascoceras, Neoptychites, Exogyra Plate 18 

Figures 1, 2. Vascoceras Mohovanense sp. nov page 219 

Lower Turonian, lower horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 

Fig. 1. Side view. 

Fig. 2. Cross-section and venter. 

Figures 3, 13, 10. Neoptychites aff. Cephalotus Courtiller. pags 221 

Lower Turonian, upper horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 
Fig. 3. Side view. 

Fig. 13. Cross-section and ventef of the external whorl of the same specimen. 
Fig. 10. Cross-section and venter of the inner whorl. 

Fiures 4, 5, 6, 7, 8. Exoyna Haarmanni sp. nov page 230 

Upper Cenomanian (?). Lowest horizon of Cerro del Macho, Hacienda de Moho- 
vano, Coahuila. 
Fig. 4. Side view. 
Fig. 5. Side view. 
Fig. 6. Small valve. 
Fig. 7. Large valve. 
Fig. 8. Large valve. 

Figures 9, 11. Neoptychites aff. Xetriformis Pervinquiere page 223 

Lower Turonian, upper horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 
Fig. 9. Cross-section and venter. 
Fig. 11. Side view. 

Figure 12. Vascoceras sp P a S e 218 

Lower Turonian, upper horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 
Side view. 

University of Texas Bulletin No. 1856 

P'te 18 



250 University of Texas Bulletin 


Hoplitoides Plate 19 

Figures 1, 3. Hoplitoides aff. mirabilis Pervinquiere page 225 

Lower Turonian, upper horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 
Side view of two specimens. 

Piure 2. Hoplitoides aff. mirabilis Pervinquiere page 225 

Lower Turonian, upper horizon. Cerro del Macho, Hacienda de Mohovano, Coahuila. 
Cross-section and venter of specimen figured on Fig. 3. 

University of Texas Bulletin No. 1856 


Avicula, Tylostoma, Exogyra, Inoceramus, Hemiaster 

252 University of Texas Bulletin 


Avicula, Tylostoma, Exogyra, Inoceramus, Hemiaster. Plate 20 

Fiures 1, 2, 11, 12. Avicula Aguilerae sp. nov page 227 

Lower Turonian, upper horizon. Cerro del Macho, Hacienda del Mohovano, Coahuila. 

Fig. 1. Left valve of specimen. 

Fig. 2. Left valve. 

Fig. 11. Cardinal margin of same specimen. 

Fig. 12. Anterior side. 

Figure 3. Tylostoma aff. ovatum Sharpe page 232 

Lower Turonian, upper horizon. Cerro del Macho, Hacienda del Mohovano, Coahuila. 

Figure 4. Exogyra cfr. olisiponensis Sharpe page 230 

Upper Cenomanian (?) Lowest horizon of Cerro del Macho, Hacienda del Moho- 
vano, Coahuila. 

Figure 5. Inoceramus labiatus Schlotheim page 229 

Lower Turonian, upper horizon. Cerro del Macho, Hacienda del Mohovano, Coahuila. 

Figures 6, 7, 8, 9, 10. Hemiaster sp. . . . page 232 

Upper Cenomanian (?). Lowest horizon of Cerro del Macho, Hacienda del Moho- 
vano, Coahuila. 
Fig. 6. Front. 
Fig. 7. Posterior side. 
Fig. 8. Left side. 
Fig. 9. Lower face. 
Fig. 10. Upper face. 

University of Texas Bulletin No. 1856 

Plate 20 



italics dpoie description of species. 

Abbreviations, tables of fossils 46, 61, 55, 67 

Acanthoffra.1 201, 221 

cfr. Choffati KOKSIUM 197 

neptvni ... 197 

prmodosoidet u. L. & f. .. 67 

J>. 44 

*i<l<r/,-/n<ili Bou'e, Lemoine and Thevenin 

67. 202. 203 

vieinale Stoliczka 202 

wwlAenae n. sp. wj, 150 

Acompiocera* .201 

Adkins, W. S. 12, 1J6, 147 

Africa, northern 42 

limonite and pyr'ts tauna "f 64, 66 

Turonian of _ 20$. 209 

AKuilcra, Jose G. 190, 192 

Albian, correlation of . 10 

fauna of 64, 66, C6 

Algeria 45. L'14. 223 

fauna of 66, 194 

Salmurian of .194 

Algiers 6, 189 

Alpine- Terlinpua road 60 

Amberleya graysonensis . _/.?;". lf.0 

Ammonite fauna, Lower Turonian . 179 

Ammonites, description of species Si, et. seq. 

pyritic or limonitic 44, 59, 60, 64, 66 

tabulation of 01 

Ammonites acceleration Hyatt 201 

arnesennis Choffat 189, 219 

conciliates Stoliczka 208 

GeslianuK d'Orbigny 202, 202 

gibboaum Hyatt 201 

Harttii Hyatt 198 

Kanabense Hyatt 201 

Kotoi Yabe 188 

leonensis Conrad 211 

Loewianvs White 208 

offaccinatuH White 199, 221 

pedroanus Kossmat 210 

pedroanus White 187. 198,~~199 

Swallovi Shumard 200 

Whitei Hyatt I~~"201 

Anrhura mttdffeana White 139, 169 

Ancycloceras bendirei n. sp. 70, 170 

linratiu Gabb 71 

inatheronianum d'Orbigrny 71 

Angermann, Dr. Ernst 179. 184. 217, 218, 223 

Aptian, correlation of 10 

Aptian-Gault 199 

Aptien age __ 42 

Aquitania, cephalopods of 197 

Area 28, 26, 28, 29, 32, 83 

VOfAltaflMil r. sp. 54, IS1, 168 

Arivechi, Sonora 26, 228 

Armstrong Iron Works 47 

Asia, Turonian of 208 

Asterisk, explanation of 46 

Asteroidea 95 

Atoka. Oklahoma 22 

Austin, Texas 19, 68, 68 

Australia, fauna of 198 

Avicula aavUerac n. sp. 190, 2S7, 252 

rjravida Coquand 180, 190, 228 

pedemalis Roemer 228 

Hacvlitea comanchenaia n. sp. 74, 152 

Bailey County, Texas ._ 25 

Bandera road 59 

Baptist Seminary, Fort Worth .. 61 

Barroisiceraa ( T) Fleuriausianum d'Orbigny 197 

Itrlemnites fibula, Forbes 67 

Bend arch 14 

Bennington, Oklahoma 17, 19, 28 

Benton formation _200 

Berry, E. W. 44. 146 

Bibliography. Ammonite Fauna of Lower Turo- 
nian of Mexico 180-183 

Weno and Pawpaw Formations of Texas 

Comanchean 146-147 

Blayac. J. 66 

Blue Mound, Tarrant County 21, 83, 65 

Blum, Texas 12, 28, 26. 40, 54 

Rochianitee Lory 75 

Bohemia, fauna of 197 

Bokchito, Oklahoma 17, 19, 28 

creek . 29 

formation 28, 29, 40 

Bom Jardin, Brazil ^199 

Bom Jesus, Brazil 199 

Boese, E. 20, 72. 146 

Boule. M. 67. 180, 202 

Branca, W. , igo 

Brazil, Salmurian fauna of- .198, 200, 210, 214, 221 

Brazos-Colorado divide 16, 22, 24 

Brazos River 21, 41, 64 

Urewster County, Texas 60 

Bruder, G. 197, 207 

Bryan County. Oklahoma 16. 27 

thickness of formations in 15 

Ruchiceras 228 

"Buchiceras" SwaUovi Shumard 202, 206 

Buda fauna 43 

formation 42, 62 

Buff marl 37 

Burleson, Texas ._ 17 

Caddo, Oklahoma 22, 29 

Caddo limestone of Taff 28, 40 

Cajamarca, province of 199 

Camacho, Zacatecas 

Vraconian of 200 

Camp Bullis, Texas 14 

Carillo. Mexico 188, 190 

Cedar Creek 64 

Cedar Hills " 31 

Cedar Mills, Texas .__12, 19 

Celendin, Peru '199 

Cenomanian 179, 190, 192, 200, 280, 28l"234 

correlation of jo 

f ? u ?? --------------- '^e^ 67 

of Diego-Suarez 208 

of Saxony 201, 206, 206 

of United States ____ 205 

Cephalopoda 68 

Cerithium 29 

Cerro del Macho 179, 190, 191, 192, 214, 218 

Cenomanian of 206, 230, 284 

fauna of 192, 200, 203 

fossil-bearing beds of ...183 

marls of 282 

Salmurian of 193, 211, 216, 227, 2297281 

Turonian of 208, 209 

Cerro de Muleros, N. M. _ 16, 17 18 19 

20. 21, 22, 28. 24. 25, 36, 41, 42, 191, 192, 200 

Chihuahua___ ig, 28. 183. 191 

Choctaw County. Oklahoma 26, 27 

Choffat, P. 186. 189, 198, 198, 218 

Christiansen, F. 68 

Chudeau, R. .__! 


University of Texas Bulletin 

Cia. Perforadora Mexicana 180 EnaUaater 111 

Cinula washitaensis n. sp 14S, 168 bravoensi Boese 17, 41, 114, 164 

Cintdia sp. 54 sp. aff. texanua (Roemer) 31, 114 

Cleburne, Texas 25 wenoensin n. sp. IIS, 158 

Coahuila, Mexico 179, 183 Engonoceras . 26, 31, 32 

Cobb Brickyards, Fort Worth 47 serpentinum (Cragin) 84, 166 

Codiopsis sp. aft. doma 44 sp. 54. 85, 156 

Coke County, Texas 26 Epiaster 84 

Colorado formation 185, 200, 205 Aguilerae Boese 109, 158 

Comanchean sea in Texas 44 subobesiu n. sp. 110, 170 

Comanche Peak, Texas 17, 24 wenoensis n. sp. 105, 160 

Comanche series, thickness 16 Escalon, Mexico 183 

Comptonia wintoni n. sp. 97, 162 Etheridge, R., Jr. 198 

Constantine, provence of 65 Europe, limonite and prite fauna of 64 

Cooke County, Texas 9, 12, 20, 22, 27 Exogyra arietina 18, 19, 81, 41, 42 

thickness of formations 15 cartledgei 18 

Coquand. H. __194. 228 c * r - olisiponensis Sharpe 192, t30 

Corbula 29, 31, 32 columba Lamarck 199, 236 

basiniformis n. sp. IM, 166 columbella Meek 230 

HUnralis n. sp ___29, 133, 16B costata 231 

Correlation of formations 10 Haarmanni n. sp. 185, tso, 248 

Cotteau, G. 146 olisiponeneis 231 

Cragin. F. W. 46, 146 8 "' aflf - arietina Roemer Its 

Cretaceous, Mexican 231 texana 16 

Crustacea, tabulation of pyrite and limonite 62 Whitneyi 17, 42, 231 

Cuesta de Huanambra, Peru 199 Exposures of Pawpaw 47 

Cuesta de Huanyanba 199 

Cummins, W. F., and Dumble, E. T 18 Facies 16 

Cvphoftoma volanum Craprin los Fagesia 196, 200, 211 

Cyprimeria washitaensia n. sp 134, 166 Boucheroni Coquand 197 

Haarmanni n. sp. 187, 111, 240 

Dagger, explanation of __ _ 45 Kotoi 198 

Dakota flora, age of _ 44 rudra. Stoliczka 187. 198. 213 

Damergou __196 superstes Kossmat 186, 187, 197, 198, 212 

Davis. John _ __ 68 tevexthenxis Peron 186, 187, 188, 197, 212 

Deba Habe, fndia _ ' 231 Fallot, J. E. 65 

Decatur, Texas .. " 14 Feli * and Lenk 25 

Del Rio, Texas _ " _58~ 69 Fhlk ' Texas 1 6 - 2 3. 24, 54 

Del Rio clay __17, 18, 19 41 63 56 69 F in'ay Mountains, Texas 16. 25 

fauna of ' 68 "5*5 26 ' 42 

limonite and pyrite fauna__ 61 boesei n. sp. - *.;, 150 

Denison, Texas__17, 19, 20, 22, 24, 30, 47, 54, 55, 68 bosquensis n. sp. . ...S7, 150 

Denton County, Texas 19, 12, 17, 30. 35, 37, 54 Fort Stockton, Texas _ 16. 24 

thickness of formations... . 16 Fort Worth, Texas 

Denton clay, fauna of 55, 60, 62 - 12 ' 13 ' 14 ' 17 > 20 ' 2L 24 . 32 - 51 

limonite and pyrite fauna of 43, 61, 62, 63 Fort " orth formation ..21, 2: 

marl 41, 46, 53, 64, 62 facies of 

Descriptions of species __68, et. seq geosynchne 

Desert sandstone _ 198 limestone 22, 62 

Desmoceras brazoense 23 Fossil-bearing beds of Cerro del Macho 183 

Diego-Suarez . ..203 Fossils, pyrite 9, 83, 42, 44. 53. 60 

Diener, C. _ 197 Fourteau, R. 231 

Dieulefit France _ __ 65 France, Salmurian fauna of... 

DouviUeiceras mammilar'e '.'. "_ 43 Turanian of 212. 223 

Duck Creek marl... ...42, 53, 54, 62 Fredericksburg division . 

fauna of 54, 60 ^f 1 ? 8 

limonite and pyrite fauna of 43, 61, 62, 63 _ thickness of 

upper and lower facies 22 F tsch, A. ..196, 197, 208 

Dumble. E. T. 146 

and Cummins, W. F. 18 Gabb, W. F. 25 

Durant, Oklahoma 17, 28, 29 Gainesville, Texas, 12, 17, 19, 20, 25, 31. 32. 47, 51, 54 

Gainesville Brick Company 31. 36. 47, 51 

Eagleford shales 1 43, 199 Gastropoda 137, 191, 232 

Echinodermata 232 Gastropods, tabulation of pyritic or limonitic.. 63 

tabulation of limonite 61 Gatesville. Texas 14 

Echinoidea 101 Geinitz. H. Br. 202 

Echinoid fauna of Washita formation 52 Georgetown, Texas 12, 14 

of Weno formation 44, 52 limestone 19, 20, 21, 41, 59 

Eck, O. 180, 195, 197, 227 Geosyncline, Fort Worth formation 13 

Edwards formation _- 24 GerviUiopsis invaginata 34 

facies 24. (White) Ill 

Egypt 214, 218. 227 Ginger shale 36 

ammonites from 180 Glenrose formation 14, 43 

fauna of 196 Globiconcha sp 140, 168 

Salmurian of 193, 196 Gongila, Nigeria .-231 

Turonian of 188, 190 Goniopygus sp. 102 

Ellenburger limestone 13, 14, 16 Goodland. top of 

El Paso, Texas 21, 24 fauna of 62 

Emscherian, the 190, 196. 200, 205, 225, 226, 228 

A New Ammonite Fauna of the Lower Turanian of Mexico 255 

Grayson County, Texas 9, 27 

thickness of formation in 15 

Grayson formation 17, 19, 29, 41, 58 

facies of 17 

fauna of 48, 66. 60, 63 

limonite and pyrite faunae of 61, 62, 63 

Graywacke 14 

Gryphea 29, 86 

mucronata 18, 19 

dilatata 20 

washitaentit . 21, 28, 29, 41 

Grossouvre, A. 146, 223 

Guillemain, C. 196 

Haarmann. E. ...180. 188, 184. 

190. 191, 192. 206. 208. 211, 217. 218, 229. 230 

Hacienda del Mohovano 179, 188 

Hamites 28. 26. 28 

quadrinodofuf Jimbo 71 

simplex 42, 69 

P 54 

sp. aff. armatvs Sowerby 69 

tinaira Adkins and Winton gg 

llamulina worthengis n. sp. 71, 162 

Harbort, E. 196 

Haslet. Texas 21, S3, 51, 65 

Haug, E. 64, 146 

Heinzia 201 

Helicocryptus mexicanvs 41 

Boese 189 

Hemiaster 180, 232 

Coirini Clark 17, 42, 114, 168, 191 

Fmirneli 228 

Meslei Peron et Gauthier 234 

sp. tSt, 252 

riovistae n. sp. Its, 160 

Hill County, Texas 20, 85 

thickness of formation 16 

Hill. R. T. 16, 46. 146 

Hillsboro. Texas 13 

Holanter sp. aff. simplex Shumard 104 

tvbglobomw 48 

Holectypus limitis 88, 108 

Homarua 62 

Hood County, Texas 17 

Hoplitoides 189. 196. 225. 231 

aff. mirabilis Pervinquiere tts, 250 

ingens v. Koenen 199 

mirabili* Pervinquiere 190, 226 

Munieri 190, 227 

niaerientw 227 

sp. 226 

Hoploparia 62 

Horizons, fossil 12 

Hugo, Oklahoma 19, 24, 29 

Huronian slates 14 

Hyatt, A. __ 201, 202 

India, fauna of _- 198, 200, 209, 212 

Inoceramus Sowerby 229 

hercynicus Petrascheck 179, 191 

Inl'itituH Schlotheim 

179. 186. 190, 192. 200. tS9, 252 

cycloide* 191 

Institute Geologico de Mexico 229 

Jack R. L. 198 

Japan. Turonian fauna of 198 

Johnson County. Texas 9, 20, 85, 61, 54 

thickness of formations in 15 

Johnston, A. W. . ._ 14 

Juarez, Mexico 191, 192 

Kamerun, Africa 189, 225 

fauna of 196 

Kanab Valley, Utah 206 

Kent, Texas 16, 18, 25, 35 

Kiamitia formation 23, 40, 68, 54 


clay, fauna of .. M 

facies ""*' 91 

Kidney shale ""."." 

Kingena ~S~f ~ 38 

Koenen. A. von ~~~. ' 225 

Kossmat, A. igg, 198~"2(>2~"2087"224 


Lamellibranchia _______ 

Lamellibranchiata ____ """227 

Lamna _________ 

Lartet, L. ........... ~" " 

Laube. G. C. . ...... ____. ""197" 207 

Lemoine, P. . ""V ion o 

Leander. Texas .:~~~"~:. T..' 18 ' 2 Jf 

Lensing, in Comanchean formations"" 
Leiocidaris . _____________ 2!)"~ini 

Leon Springs. Texas .. 
Liddle, R. A. ____________ ~ 

Limonite and pyrite fauna of Africa""" 

of Europe ____________________ 

of Madagascar . 

of Texas ........... ----- 

summary of ... 
Lisson, C. I ....... . a 

Lithological changes .. ' , 

Loew. Oscar _________ """208 

Love County, Oklahoma 

Lunatia sp. ---------- '"il'Ttn" tfta 

McLennan County, Tas "-Tr:.".".".'.".'!! 86, 64 66 
Madagascar ---------- 209 9nv 


pyritic fossils of 

2 2 ' 

Mainstreet limestone .. ~rrr~""48,"V7","BV 59 

facies ~_ f- }jj 

fauna of 

sandstone in 

Mammites ~" " 2o6""221 

cfr. cranaitetta Stoliczka "197" iqs 

conciliates ""107 } 

Fntech i"."~~ lm 

Steliczka _ ~"fBR~~9n7~~on< 

-186. tot, 236 

Laube et Bruder. emend. Petrascheck""" "_tna 

Mohovanenng n. sp. 186. toe. 220, 286 

nodosotden Schlotheim. .186, 197, 198, 199 207 208 

var. Afra Pervinqniere ' 199 

Mantelliccras 201 

Mariscal Mountains, Texas fg~ 41 
Marshall County, Oklahoma ___IH" 

thickness of formations 

Medina County. Texas " 68~ 69 

Meleagrina ' ...i s 

Metoecoceras .. 19l" Mn""9ni""->n9 

aff. Whitei Hyatt 

Geslianum Petrascheck 

sp. nov. . ig s> 192, t'os, 2S5 

^VIMei* 2 2 '' 20S 

Metopaster 'hortensae Adkins" "nd'wfnton "" 97 162 

Mexico _ a-,* 

and West Texas IIIIII_II"i; 41 

Mornasian 228 


n - P- 1"-~ ;ilir"l60 

worthense 43 

Mungo region, of Africa "_19e""226 

Myra, Texas _!.!____ 13 

Nacreous fossils, Weno 26, 44. 64 


NautHiu sp. gg 

texanua fc . r , ., j 

Neoptychites -"-"-V."."."_".V."."l967200,' 221 

aff. cephalotus Courtiller 189, ttl. 248 

aff. xetriformix Pervinquiere 179, US, 226 248 

erataus Solger igg 

telingaeformis Solger " 139 


University of Texas Bulletin 

Telinaa Stoliczka 189, 198, 223 

xetra 224 

xetriformis 189, 222, 224 

Nerinea sp. 

Nerita sp. *** 168 

Neritina sp. . 168 

Nigeria, fauna of 196, 209. 214, 227, 231 

Nodosaria texana 18, 19, 28, 32, 34, 41, 146, 170 

Noetling, F. 146, 197 

Noland's River 

North Central Texas 

North Denison sands _.: 

Northern Europe, fauna of - 

France, fauna of 

Germany, fauna of 

Tunis, pyritic fauna of 66 

Nucula 29. 31, 3: 

nokonis n. sp. 118, II 

wenoensis n. sp. -. . 1*0, 168 

Oklahoma 40 

Opal, Zacatecas .60, 191 

Ostrea(Alectryonia}quadrir>licata Shumard _ 


carinata ? Lamarck . 

columba major 193, 194 

foisseyi Lemoine _. 6 | 


quadriplicata 20, 28, 29, 31, 32, 36, 41 

sp. aff. diluviana Linnaeus -- 



Pachydiscus peramplus _ 



Palestine, fauna of _ 

Paluxy sand 

Parker County, Texas, thickness of formation-- 16 

Parras, Mexico 229 

Pawpaw formation 9, 41, 42, 43, 51. 53, 60, 62 

clay facies of 32 

correlation of 1, 40 

facies of 11. 20, 26. 27 

fauna of 44, 45, 60-63 

fossils 9, 10 

ironstone of 

limonitic and pyritic fauna of 61-63 

lithology 26, 27 

location of outcrop --9, II 

marl facies S< 

thickness 26, 26, 33 

changes in 10, 12 

sandstone facies 

shales 45 


Pecos, Texas 1? 

Pecten - 29, 33 

georgetownensix (Kniker) _ 

inconspicuus Cragin 123, 170 

mbalpinus 17, 29, 31 

Pedinopsis symmetrica (Cragin) . 


Pelecypods, pyritic or limonitic, tabulation of 63 

Peltastes sp. ._.102 

Pennsylvanian strata .--18, 14, 1 

Pentaceras ainericanus n. sp. 3.9, 162 

Pentagonaster teitnsis Adkins and Winton S5, 162 

Peron, A. 6, 194 

Peru, Salmurian fauna of _. . 199, 200, 214 

Pervinquiere, L. 42, 

45, 64, 66, 146, 189, 194, 196, 208, 212, 221, 222 

Petrascheck, W 186, 186, 197, 201, 202 

Petrographical horizons 183 

Phyllocr.raa forbexiatium d'Orbigny : 67 

diegoi Boule, Lemoine and Thevenin 67 

Pinna 33 

yuadalupe Boese 41 

Placenticeras 226 

Placonmilia 63 

bravoensis 41 

mexicana 41 

gp. 41 

Plicatula sp. 29 

Polytechnic well. Fort Worth 13 

Porto dos Barcos 199 

Portugal, fauna of 196, 209, 214, 217 

Turonian fauna of, 186, 187, 188, 193, 212, 218, 221 

Pre-Cambrian strata --. 18. 14, 16 

Primrose, Tarrant County 54 

Prionotropis 202 

Woolgari 197, 211 

Protocardia 34 

multistriata 20 

p. aff. mltistriatum (Shumard) 1X6, 168 

sp. aff. texana 20 

texana 17 

Protozoa 145 

Province of Sergipe, Brazil 199 

Pseudaspidoceras 196, 198, 200, 231 

aff. Footeanum Petrascheck 186, tOS 

aff. pedroanum White 187, 209, 238 

Footeanum Stoliczka 186, 198, 199, 209, 210 

pedroanum White 210 

aalmuriense 197, 209 

sp. 227 

PfteudotisBotia Douvillei 197 

Ptychoceras 69 

Ptychodun ' 63 

Puzosia Austeni 197 

Pyrite ammonites 42, 55, 66, 58, 69, 60-61, 64-67 

fauna, comparison of 53 

of North Texas Comanchean 53-67 

of Pawpaw formation 44.47-53 

summary of 60-67 

Pyritic starfishes 54 

Quarry limestone 29, 31, 32, 35, 36, 37 

Quihi, Texas 68, 59 

Red River J 64, 55 

Red River valley 19. 20, 21, 27, 36 

Reed Plateau, Texas 59 

Regularia 62 

Remondia 32 

Remondia? acuminata (Cragin) 1S6, 160 

Rhone basin 65 

Richardson, G. B. 147 

Riovista, Texas 12, 20, 25, 51 

Ritter, Frederico 183, 211. 218 

Roanoke, Texas 17, 18 

Roberts, Jno. R. 41 

Roemer, F. 228 

Round Rock, Texas 19 

Rudistid facies 17, 24 

Runnels County, Texas 25 

Sahara desert, the 214 

Salenia sp. 

Salenidae 62 

Salmurian, faunas of, 186, 199, 194, 195, 196, 208. 

211, 212, 213, 215, 217, 218, 219, 227, 228, 231 

Santonian 228 

Saumur, France 189 

Saxony, Cenomanian of 186, 209 

fauna of 197 

Saxony-Bohemia, Sa'murian of 200 

Sayn. G. 64, 147, 202 

Scapkites .-26. 2: 

aefjualia 42, 67 

Hilli Adkins and Winton '9, 162 

sp. 54, 69 

sp. aequalia 43 

wortkenftis 16 

Sch'agintweit, O. 199, 200 

Schlvcnbachia 211 

A New Ammonite Fauna of the Lower Turanian of Mexico 257 

ftobieiuu _.> 48 

in/lata - 42 

manteUi 48 

sp ._ 17. 23 

trinodosa 23 

rarian* 43 

wenoennif n. %v. 89, 160 

wint&ni n. sp. 90, 164 

Schweinfurth. collections of ...195 

Sellards. E. H. 14. 147 

Senonian ...179, 190, 19, 200. 228 

Shafter, Texas 16. 18 

Sharks, remains of 68 

Sheffield. Texas 16, 24 

Shuler. E. W. 62 

Sierra Blanca. Texas 16, 26 

Sierra Mojada. Mexico _ 183 

Sladen. P. 147 

Slate, Pre-Cambrian _ 14 

Solirer. Fr. 194. 196. 198, 226 

Solitario. the _ 68. 60 

Sonora. Mexico 18 

South America, Salmurian fauna of 198. 208 

South Bosque. Texas _ 19, 68 

South Bosque River 5V 

South Central Texas 40 

Southern France, fauna of 197 

Sahara, fauna of 196 

Spain __^ 214 

Spencer, W. K. 147 

Stanton 201, 205. 206 

Starfishes, pyritic 54 

Ste-nonia sujifrnut iCnmini 62 

Stephanocera* 212 

Stephenson, L. W. 20. 36. 40. 46 

Stoliczkaia 202 

Stoliczka. F _. 207. 223. 224 

Stratitrraphy 13. 183 

Sugar Loaf Mountain. Bryan County. Okla- 
homa 28, 29 

Sulphur Creek _. 29 

Sycamore Creek _-_33. 38. 39, 47. 51 

Syria, fauna of 197 

Szjanocha. L. 43, 147 

Tah'e of fossils: 

of Del Rio clay 58-69 

of Denton clay _.i. 66 

of Duck Creek formation ._ 55 

of Grayson marl 67-68 

of Pawpaw formation 51-52 

of Weno formation 48-50 

pyritic and limonitic _61-66 

Taff. J. A. 29. 30 

Tarrant County, Texas _ _ 

9, 12. 20. 23. 33. tt. Yl.'l't. 55 

thickness, of formation ._ 15 

Terliniroa. Texas ._ 16, 58, 59 

Creek _ 60 

Thevenin, A. 67, 202 

Thicknesses, of Comanchean ~~. .. 15 

ThomajtitfK " 196 

Tishominfro, Okla 

Tifiaotia spp. 44 

Trapichc das Pedras Velho, Braiil... !IIl99 

Trigonia 29, 32. 179 

Trinidad mine ' go 

Trinity division, thickness of ] '~_ 15 

TrofhoKmilitt gjj 

Trochus laticonicu* n. sp. ~~lYs~~168 

Tucumcarii. N. M. __18 '0 

Tunis 46, 66. 187. 190. 196, 212. 214. 221. 223 ' 2~> I 

fauna of 194 

Turonian .-205. 2fi 208 

209. 212. 213. 215. 217, 219. 221. 223. 226' 228 

correlation of 10 

of Mexico V 179 <"> 

Turonian. Lower, Ammonite fauna of-.. '_ 179 

TurninK point of outcrop Id 

northern, at Orlena, Cooke County 27 ' 

southern, Bexar County 19, 21, 24 

Turrilites 26, 28 

bo8iiuvnnix n. sp. 76. 164 

brtuotnn* 19, 31, 38, 41 

sp. 33. 64. 69. 7S, 154 

worthenttig Adkins and Winton 78, 154 

Turritflla 28. 29 

t/rayttonennia n. sp. ~14<), 168 

p. 54 

U'orthcnnin n. sp. 141, 168 

TyloKtoma ovatuin 232 

Type collection 68 

Udden. J. A. .. 14 

Union Station, Denison " 47 

United States, Salmurian lacking in 199 

Turonian fauna of 199 

Utatur trroup, of India 187, 212, 224 

Valangian 61 

Voscocxro* 196. 213, 221, 231 

adonenne 186, 187 

aff. adonense 214, 216 

aff. arnesenae Choffat 214 

aff. Gamut Choffat 214, 216. 242 

amieirense Choffat 199 

Angermanni 219 

sp. nov. 214, 216, Sir, 244 

Caudini 196 

Douvillei 214 

Durandi 193 

ex. aff. Gamai Choffat IIIIIlSS 

Gamai 213. 216 

Gongilentte Woods 227 

Harttii Hyatt ". illzil 

harttiiforme 214 

KoKsmati 179 

mohovanenae n. sp. 189, 214, SIS, 248 

Mundae 216 

n. sp. ex. aff. V. adanense Choffat 114, 240 

liolynioriikum Pervinquiere 189. 199, 220. 221 

sp 189. tlS, 248 

Hubcanciliatum 214, 220, 221 

Venericardia wenoennis n. sp. 125, 160 

Von Koenen, A. 225 

Vraconian. correlation of 10 

faunae __ 23, 42"".~66,~~66~, 67 

of Arivechi, Sonora 228 

Waco __67, 58 

Wadi Am Rimpf ...231 

Walcott. C. G. __205 

Washita division 42, 46 

fauna of 43. 44, 52, 64. 60-62 

thickness of 15 

Weno formation 9, 20, 33. 43, 46, 61, 62 

correlation of 10 4(1 

facies n, 20, 26, 27 

fauna 45.50 

fossils 12 

ranjre of 46 

table of 48-60 

litholoiry 26. 27 

location of outcrop 9, 10 

sandstone in , .' 20 

stratigraphy of ~ 13 

thickness of 26. 26 

changes in 10, 12 

West Texas 41 

and Mexico ._ 41 

Whitney. F. L. 102 147 

Winton. W. M. 9, 28, 32. 33. 146. 147 

and Adkins .. i r, 

Wittich, E. . IIIIIIIIIIIIIzil 

Woodbine? flora 44 

Woods, H. 1M, 227, 231 

Yabe. H. igg 

Zacatecas. Mexico go 





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LD 21-50m-4,'63 
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